I'm trying to encourage as many people as I can to run it, or at least play with it for some while to gain familiarity with it. Properly applied, I think it does add quite a bit of useful practical security... though it's not going to automatically solve all problems. I like the silos of compromise, at least, and you can do high risk things (like "anything web") in disposable VMs that reset on VM power cycle.
My only major concern with Qubes is that I've not decided if it's weird and niche enough to be mostly left alone by the 0day markets, or if it's a super high priority, high value target to attack because of the type of people who are likely to use it. I'd like to see an ARM port of it, because Xen on ARM is quite a bit simpler than Xen on x86, but the hardware to run that doesn't quite exist yet. Maybe with the RK3588...
The fundamental problem here is that software developers (and I'm guilty here too, as much as anyone in that industry) tend to view complexity as a one way ratchet function - add features. Add features. Add features. Add knobs. And when it comes crashing down around your ears, "add security" (in the form of sandboxes, or process isolation, or... https://xkcd.com/2044/ applies here).
And then it turns out that "adding complexity to solve problems created by complexity" isn't a strategy with a great long term success rate.
I'm slightly encouraged by Apple admitting, as clearly as they ever admit anything, that this strategy isn't working - with their Lockdown mode, that's "only for people with the most extreme threats, blah blah blah," and I'd expect anyone in the security or software industry to turn that on basically as soon as they get iOS 16 and not look back. Or install the beta to give that option.