It is dead in the sense that it essentially has to be a non-mechanical optional feature at this point, rather than something that's built into the mechanics, which is a big change from earlier editions of D&D.
It's also more divisive, opinion-wise, than a lot of elements, in that people who are against it or for it tend to be more strongly so. Further, I don't have figures, but I strongly suspect that it's drastically dropped in popularity over the last 30 years. Like, had you polled a D&D forum in, say, 1995 (if one existed - I was all about Shadowland.org, the WoD forums and RPG.net and stuff back then), I suspect we'd have seen alignment at like 80%+ support. Then in say 2005 it'd be down to like 65-70% support, then by 2010 maybe 50-55%, and now here we are with 46%. I don't think that trend is likely to reverse.
Sorry, I read this and it seems kind of mean. That isn't intended - you're totally entitled to love the hell out of it! What I'm trying to say is that it's a feature that it is necessary to exclude from being mechanical, and that is only likely to continue to be pushed to the periphery of D&D as time goes on.
On the topic generally I find it pretty interesting that reddit through ability scores were the key defining trait of D&D moreso than, say, classes, or levels, which seems pretty wild to me. I can play a game that feels exactly like D&D to me with different ability scores or none, but I can't do that without classes (I can do it without really proper levels, as Dungeon World shows). YMMV.