Ya, I think some people are really missing the point.
No one is posting threads there for people who couldn't get the vaccine. No one is posting people who quietly sat back taking some precautions but didn't get the vaccine. No one is even posting people who quietly refused to mask and didn't get the vaccine. There's very little there to post.
What is being posted are hateful people who spread their hate and ignorance for a year or more before it finally caught up to them. Were they victims of misinformation? Sure. They also were the misinformation. They were actively a part of the problem, not just victims of it.
Reading the subreddit regularly, its also worth noting that I don't think the Slate article characterizes the reactions of the sub very well. Is there some schadenfreude behind it? Absolutely. Some feeling of "Glad I wasn't that stupid"? Sure. Its not the overwhelming vibe of the place though unless that's specifically what you're looking for. Some people make jokes and laugh at the ignorance these people were spreading, but few are directly laughing at their deaths and those are rarely the comments that rise to the top in threads. Its a lot more people being sad for their loved ones. Frustrated that their kids are now orphans. Disappointed that the ones who had finally seen the light and wanted a vaccine when they got out of the hospital never got the chance.
That's the biggest misreading some here are suggesting. Most of the people in that sub don't want anyone to die. I know I don't. If they did, you wouldn't see so much joy and excitement at the people who were finally convinced to get their shots.
People are dying regardless though. If it is going to be someone, I'd much rather it be the people who refused to protect themselves. Who actively endangered others. Who were vile, hateful bigots. And ya, sometimes the more vile and bigoted ones I think the world is probably a better place without them in it, but even then I didn't wish death on them. I would have far preferred if they just got a free vaccine so they could live. So we could all get back to living our lives. When I pull up a thread my thought isn't "ha ha, look at the dumb dead idiot." It's usually a sigh, with "what a moron." Or often "What a moron, their poor family." Sometimes even "That poor moron" in the better cases. That subreddit is mostly a hate read for me and it seems from the replies for many others that's a pretty common feeling. People aren't going there to feel good.
All the while though I think its actually doing a lot of good. For a lot of us, this is one of the more direct looks we've gotten at exactly how these people are dying at this point, directly narrated by them and their families. Not reliable narrators of course, but there's enough commonalities between cases that you can start to see some of how this really goes. We've hidden the deaths away to a degree that seeing it this directly in the words of those dead or dying is quite powerful and if the people showing their new vaccine cards are any indication, I'm not the only one who feels so. Some of the testimonials by family members, by doctors, and others have been really useful. And frankly, I think history will be fascinated by this period and how so many people actively killed themselves for political reasons. I think its important to document.