People seem to really dislike Destiny 2. Why haven't they ended it yet?

Destiny definitely isn't in its greatest state right now (and honestly, hasn't been in a while).

The answer to why they haven't "ended it yet" is: Because it still makes them money.

Realistically though, if you look at any big discussion for a game you'll always find people who dislike it (because they tend to be louder than the people who are spending their time playing the game instead).