I think a lot of people are forgetting that on tumblr fandom used to be practiced very differently. now everyone fucks off to their discords or tumblr groups to discuss everything with a select few, making tags be nearly only used for posting some finished fanworks or not at all
a decade ago people didn't have tumblr groups. people didn't even have dms. if you wanted to talk to anyone about anything you had to make a post, or send an ask (which more often than not would get published and thereby become a post in the end too)
so next time you think "I have a fandom thought but I have to find a small group of hyperspecifically like-minded people to share it with in private" remember all the freaks you could be missing out on meeting by keeping the tags dead. use tags, make friends. fuck discord.