Bandwidth and hosting still cost money, period. And why would 20 be laughable? What would be okay by your book? 50? 100? 1000? 20 per day is fine for most users, how much content are you downloading every single day that it wouldn’t be?

Sure, if you don’t mind storing stuff and then never reading them again.

I use it as a backup location for pictures and videos I make with my phone and for bookmark storage. But you can use it to fully replace cloud services like OneDrive, GCloud or iCloud.

Neither does NextCloud. Self hosted bookmarks have been great.