There's a bunch of different things that will happen that will ruin your enjoyment of anime, ill try to mention some
>Eventually running out of anime to watch
In my experience the only people who still like anime are the ones who haven't watched enough yet. There are some rare cases but those fall into sunk cost fallacy.
>99% of anime watchers are cancer posers
The anime fan base is cancer. There is no difference between the types of people who watch anime anymore, the average /a/ guy is as much of a normie as the /jp/ otaku, and both are as cringe as the high school narutards
>Anime has become a mainstream commodity to consume
You will not find anyone anymore that actually enjoys anime. It's going to be just people who either watch anime for le epic otaku e-cred, to update their anime list, or to brag about how much moe or shounen they watched.
>Anime is a flawed medium
Eventually you will get tired of 12 episode VN shilling, seasonal garbage that the masses seemingly eat up. The 50 year old wagie succ that does voice overs for your loli moe that you didn't care about before will start to taint the pure image they are trying to portray. The storylines all end the same and end abruptly, if you get involved in a long series the writing is Marvel capeshit tier even in the most "mature" artpiece titles, with retcons, red herrings, and deus ex machinas out the ass. It doesn't matter if you're watching shounen, moe, seinen, or 2deep4u…they all share these flaws.
>The genius writers of good anime from old days are now bitter corporate shills who cant create anything original.
Anime has lost all it's creativity. There hasn't been any new or interesting trends. Original works are a thing of the past. Everyone is too afraid of making something new and failing.
P.S I love anime. Im a real anime fan and saw years worth of anime, but to keep watching it knowing all this I simply cant just "not care" as I don't derive some sort of masochistic pleasure from watching garbage.