I was a huge reddit user over the years, but now I only go there for a handful of very specific subreddits. That's really it's only use anymore. It's great for that, but they are probably seeing massive decline in usage.
And the moment they basically kill 3rd party reddit apps is the day I barely touch it again.
You're likely not using TikTok effectively. I personally use it, and all my engagements with it are 100% relevant to my interests.