I found an interesting discussion on Reddit: https://www.reddit.com/r/btc/comments/agckng/why_is_nobody_using_memocash_anymore/
It discusses that memo is in decline https://memo.cash/charts and is down to about 4 active users per day (if I am reading the middle chart correctly).
The top comment on why memo isn't being used is because it costs money to post. I would agree that this is a problem with that platform. It is also why I want to keep posting and groups free to create. And users earn BTC via others actions, which translates to "buying" a better social media platform.
I continue to think about this and I am finding that the formula for ZapRead is much better than what I've seen out there in other projects.