I think the value proposition here is to encourage more of an actual free market for "banks" or "mints" themselves. ecash is not a trustless solution, but it does reduce the barrier to entry for a group of individuals collaborating to participate in a global economy (a la Fedimint). They've got to run their software, secure their hardware and fund the mint. The value proposition really shines when the participants are locally proximal to each other -- like a neighborhood or local community. If/when the trust breaks down, things can be settled face to face, and over lightning, it should be almost painless to move to a new mint, or migrate funds up the scaling layers ecash -> lightning -> bitcoin if one is feeling insecure about the community or suspecting a bank run. And that's not to mention, the elimination of regulatory barriers to spin up a new financial institution.
Again, it's not a perfect solution, and it has me still with mixed feelings WRT the sovereignty maximalist voice, but it does seem to be an experiment worth tinkering around with. I'm reminded of the supposed origin ethos in the creation of Craigslist, given all the concern about meeting up IRL with "random strangers on the internet" -- that he believed "people were generally good to each other". Perhaps instead of trusting absolutely nobdy, it is a benefit to have easy options to choose who to trust, like family, friends and local community.