The realism I was talking about was that which is obtainable through the conventional mediums outlined by introductory books, particularly graphite and how to shade with it. Anime artworks are shaded mostly with cel shading, halftone shading, or no shading at all. None use the grain of the paper to any effect and It's safe to assume those looking to draw anime or cartoon styles these days will deviate towards using digital tools so working with classic mediums can be skipped. Of course it's still wise to learn conventional media especially because it's so accessible, but someone's ability to realistically shade a sphere with a pencil won't be reflected in any anime/toon style artworks they produce so such basics can be skipped if stylized drawings are the end goal of the learner.
>since anime is based on reality and is a stylized from of it, you can never really improve just by drawing anime
That sounds like advice given by someone who believes replicating reality to be an objectively better goal than drawing anime styles, as if they're assuming that realistic images are what you truly strive to draw while anime is just a milestone on the way there. If anime is what you wish to draw, then there's no sense learning any skills more advanced than those necessary to produce anime styles. Consider this: What is a nicer drawing to behold?An amateur drawing of an anime succubus with uneven eyes, strange proportions, misshapen clothes, and bad perspective BUT is shaded very realistically with proper light bounce, shadows, and scattering… The Deviantart special.
ORAn unshaded, untextured, basic line drawing of an anime succubus who is drawn consistently within herself, with proportions that are either believable or appeal well to an emotion (Does you brain recognize her form as cute, sexy, cool, etc), who scales well in to her environment - Like in a typical manga
The second is the prevalent case for published works. Now if you've got infinite time to work on a single drawing and you wish for it to have realistic shading, then knowing how light, fabric, color, and all that jazz works is going to help a lot. But lacking such knowledge isn't going to make drawing the basic anime succ any harder. Take Konata here for example. Consider the scale of her eyes and head, the obtusity of her hair, the lack of muscular representation, the chunky wrists, 404 nose.. the list goes on. Despite these far stretches from reality and simplified shading, she does indeed look good (fact). No deep knowledge of realistic proportions, shading, or texture contributed to her design. She's drawn well with no help from realism. That's just a style though. You may want to draw anime succubi with realistic proportions who are shaded nice and pretty. But because it's anime style, there are more important rules to follow than that of realism.
If anime is your end goal, then aim directly for it and nothing else. Observe existing anime images in styles you like and take note of what makes them look good in your eyes. Visualize an anime succubus image you wish existed and let the pencil fly to your best understanding of how to produce the image. When it doesn't turn out how you envisioned it, step back and examine it to see what is off. Then study more that aspect of your desired style and try again, applying what you learned through attentive examination of the one aspect that you wish to fix. If you look at anime succubi pics a lot, then you already know subconsciously what makes a good or bad drawing of one, and through testing your visualization capabilities and how well you can translate mental images to paper, you will bring the knowledge of what is and isn't the right thing to do when drawing that style to your conscious mind. It will be hard, it will take time, but if drawing anime succubi is what you desire, then every time you step back, see something wrong, and then correct it, making your image closer resemble how you envisioned it would, then you will become rewarded with a rush of dopamine, having learned something that you wanted to learn, that brings you closer to creating what you want, all on your own by simply grabbing information from the backroom of your brain and using it to entertain yourself. Every line you draw of an anime succubi that looks good will be a line that is fun to draw. If you're tackling a desire of yours head-on , every step closer to your goal will be its own reward. Then, when you are capable of producing images to your liking, you can experiment with the skills not essential to producing a passable anime succ pic. Experiment with different shadings and compositions, grab physical attributes of 3dpd and translate them to 2d to develop your own unique style. Simplify some things and see if it helps you to make succubus pics faster and easier while still looking good as anime drawings.
If you start drawing something that you're NOT interested in - realistic shading, fleshy ugly bodies, boring environments free of nekomimi maids - your successful exercises won't be pictures you enjoy looking at. If something looks wrong you won't be able to pull the solution from the back of your head. This is because you don't expose yourself to realistic drawings as much you do anime ones. You've not developed an interest to produce realism nor a mental library of information on what looks right and wrong in a realistic drawing. You're not critical of reality as you are of anime, so the only way you'll know if your drawing looks good is if you compare it directly to the example in the book's lesson. And bam, you just got trolled in to drawing some boomer's shaded sphere oc without even receiving commisionbux.
>So, how deep into realism I should dwell, if at all, to finally be able to draw cute anime succubi?
Realistic enough for your goals. Want your anime succubi to have realistic musculature? Study musculature. Attempt to draw realistic muscles. See that it is wrong, come to understand why it is wrong, rework it until it looks right, then remember what was different between the wrong and right versions and consciously apply that memory next time you draw realistic muscles. Want their hair to shine and flow? Study real hair, attempt to reproduce it, look at nice hair 2d pics and figure out how other artists managed to portray lovely 2d hair. Study as you go but seek your existing subconscious knowledge first. Figuring things out on your own and ending up with a nice picture because you did is an incredibly rewarding experience.
>because anime artists did study those basics after all.
But do you see them applying that knowledge? Rarely, because it doesn't interest them to do so, as the anime style appeals more to them, and a truly skilled artist only draws what he wants to see. Don't try to draw what you don't wish to look at, even if it comes out good it will still disappoint you, and you're the only person who you need to impress right now.