I agree with the sentiment, but there is a devils' advocate argument:

Most compute loads are bursty. Most PCs and phones sit idle almost all the time. It's an inefficient use of capital. In the cloud you can be idle and then suddenly command 1000X more power than any affordable PC could ever have... for 10 seconds... then be idle again. Those kinds of work loads aren't possible to realize on a PC without massively overbuying hardware.

I'd like to see more research on secure private cloud computing. Homomorphic encryption has gotten better but is still very slow, but there's other approaches that can help quite a bit but don't require much of a performance hit. Look into secure multiparty computation, reversible anonymization, etc.

I don't think personal computing will die, but I think it'll go back to being a hobbyist and pro thing like it was from its birth in the 1970s up until the middle 1990s. In the 1980s the average person did not own a computer, or if they did it was just to play some games. The average person was not loading BASIC programs off bootleg tapes and calling BBSes.

BTW I've been thinking a lot lately about how AI could save personal computing by allowing us to create an off-ramp from the present rats nest of complexity to something saner and simpler. Just thoughts right now but it's interesting.