I'm gonna bring history on this! Yes, it's very true that 'almost noone' as history suggests. We can see with many other things. For ex. Internet prevailed because people got it easier to access and use as the days went by. More and more people want Bitcoin in the easier way. Not everyone would be sound in technology to do self custody. People who say that Bitcoin is only for the 'people who are willing to learn', I don't agree. If you want something for everyone than you should have something that doesn't get bias on the basis of knowledge. The easier it is to use, the more prevalent it would be. Custody does solve it. There will always be more people who do not wish to learn.