That is an interesting thought.

How do you make self-hosting appealing to more than weird nerds?

Make it a comprehensive service you can rent at a fixed monthly cost. Which of course defeats the whole "self-hosting" part.

Regular people don't like the Magic Box Which Makes Things Work. They'll begrudgingly shove it in a cupboard and plug it in, but even that is already asking a lot. If it needs any kind of regular maintenance or attention, it is too much effort. "Plug in a harddrive once a month for backups"? You'll have just as much asking them to fly to Mars and yodel the national anthem while doing a cartwheel.