In our small company we tried a self hosted Nextcloud instance and we ended up moving away from that after years of pain. Now we are in HedgeDoc, that is neither ideal because of its lack of central way to manage files collectively, etc. So, I guess good news.
In everyday life as an adult, they just don't have the mindshare that the big clouds have. I default to Google Workspace for everything (or whatever it's called now) because that's what everyone else in my social circle use and what most employers use, and being able to seamlessly share stuff with other Google users is much lower friction than trying to get them to sign up (much less pay for) yet another similar service. The network effect is more important than any minor difference in technical merit...
A client who was using Google scheduled a meeting that I was invited too and I put it on my calendar. Then somebody had to move the meeting but didn’t click the option to send an update when they did.
Everyone’s Google calendars updated. My Proton didn’t because they didn’t send the update. Everybody else was on time and I wasn’t, making a terrible impression.
In investigating, I found that my Google calendar that had been setup prior to the Proton move also had the update even though it wasn’t on their domain.
That is the network effect in action.