What I'm about to say is going to sound like I disagree with you in spirit, but I don't think I actually am disagreeing. Despite using reddit for a specific thing when you made this post, you also just… didn't really give a fuck one way or the other. You could take or leave it, and for now, you chose to take it while it made sense and benefitted you.
There was a time when sites and apps (or "programs") didn't have so much longevity. No one really blinked when people stopped using the IM services. They just logged on while it made sense to because their friends were active, and then one day, they didn't log in anymore. No one thought twice when Napster was overtaken by KaZaA, or when that one went away for Limewire, or any of the other host of P2P services. They used them until broadband Internet became ubiquitous, and then they went to bittorrent. MySpace went quietly into the night and was gradually replaced by Facebook. Both of those (and their predecessor, Xanga) replaced the old geocities/tripod/angelfire personal websites. From my youth, Google is the only giant that remains.
Seeing the way people act about Twitter and reddit make me realize how much the standards have changed. It doesn't have to be a big event. This is nothing new. These things wane as they meet better, more efficient, and more user-friendly competition. This is no different. No one has to weep for it or give a concerted effort to make it change. The fedaverse options are modeled after a similar UI, it won't be such a big adjustment if people just let it happen and stop trying to save a corporate corpse. We used to not care about preserving the familiarity of failing services, and we were all the better for it. I think everyone could benefit from taking a page out of Web 1.0's book from time to time and inject a little more of that Wild West energy we used to be flush with. I know things can never be like that anymore - for good reason - but seriously, just stop giving a flying fuck about reddit in any capacity. It's making less and less sense to use it, so now we have this. One day, less and less might be zero, and that's an OK and natural progression.