Aren't Phoenix, Breez and Blixt trying to accomplish some kind of a semblance of self-custody?
No mobile app with lightning functionality does that, unless you're running node / hub from home.
Bitcoins were made to be spent, not held. The ability to spend them is what gives them their value. When you spend your bitcoin, you are fulfilling its purpose, its destiny.
Money, in general, is made to be spent. Spending your savings fulfills their purpose, but you should obviously be cautious on when and where to spend them. Same as with bitcoin.
If everybody held their BTC
Everybody
don't hold bitcoin. That's what matters. What would happen if everyone did, is another story. The fact is, if you're living off the basic income, need cash and you're out of liquidity, you're going to sell your bitcoin. People who don't run out of liquidity (i.e., rich), with the same mindset and reasoning, will probably hold them for longer.