> Can I ask why?

I dislike the way flatpak is effectively a second distro on top of whatever else I'm running; it eats a rather lot of additional disk space (and network bandwidth), requires that I run updates for it in addition to everything else, and I'm not sold on its security patching story (last I looked, it strongly favored everyone effectively vendoring most dependencies and I don't trust them to keep up with patches like my actual distro).

To be fair, there's also a list of reasons I do like it, just... both pros and cons.

> It was tiring getting bug reports that were only reproducible on certain drivers and setups

I'll give you userspace, but drivers should be like the one thing that flatpak doesn't help with? It's the same kernel, not a VM.

Not someone you asked, but I personally tend to avoid it because it makes my system less transparent to me.

Isolated self contained containers are cool for enterprise setting with huge fleets of machines, frequent updates, etc. But it's not optimal for desktop Linux atm because no one secured any of desktop APIs and there are no easy way to inspect WTF each container is doing and why. Is it ships outdated deps? Is there crypto miner in or its just random hung process eating 100% of one cpu core?

Basically each app in self contained container have its own universe and you will never figure out what exactly its doing. So its turn your system into a black box.

As maintainer of OSS software and game developer I totally get the appeal, but as user I love Linux exactly because it's give me more transparency and I dont want to lose it.

I have no idea if all flatpack apps update their own vulnerabilities once they are discovered. The distribution usually does it. Then I hate the idea of having boundaries between apps and imperfect integration with the desktop environment. Furthermore I don't really need any app distributed as flatpack so far, so I don't care. When I see one I only miss giving it a try but I don't miss using it to do my daily job. I could even said that flatpack is a good thing for me because it encapsulates all the possible distractions and makes them unreachable.

Anyway, I'd rather use flatpack than snap. I left Ubuntu for Debian because of it. I hope it goes the way of the other Canonical's unsuccessful attempts at building their own proprietary system and moat.

Not the parent commenter, but I feel it mixes sandboxing and a non-ideal packaging method together.

Something like nix solves the second problem so much more elegantly.

I read through the commenters who responded before I saw your question this morning and feel they all did a great job with their answers and agree with them.