1. The vast majority of Reddit users (maybe not the contributors) use the native app. I myself do as well. So this api change doesn’t affect me immediately (of course it does indirectly by restricting moderation and bots).
2. I open Reddit today and it’s different but not inferior. I’d argue the real value of Reddit nowadays is in all the nice subreddits one subscribes to, and most of them are still alive and active. My friends who just started redditting last year have not even noticed the whole shebang.
It’s very possible (in fact slightly more possible than not) that Reddit will survive this mostly unscathed. I’m not betting on it but I’m a poor speculator so don’t take my word for it for sure.