I read "it's dying" by people on Discord and Reddit all the time, but the numbers prove otherwise. It's been going up this entire time and sitting over 3 billion MONTHLY ACTIVE USERS!
I feel like the bubble around people on other platforms saying "who uses Facebook anymore lol" is kind of wild given the numbers. Keep in mind these are active users not just abandoned accounts.
Now, consider how powerful Reddit is/used to be, especially in quality human generated resources (jokes, answers, commentary etc) and realize networks exert power in different ways from just numbers. Numbers matter, but in very different ways.