Agree in general. The problem for me is not that they have an app signing process ... even if it's bad. The problem is that removing users' rights to execute programs (as per Stallman's framing) is profoundly morally wrong.
Discussion
macOS let's you jump through hoops to still execute whatever you want (they just want to stop most newbie users from doing it). I can't imagine windows doesn't have that option but I don't use it and have no experience.
Defender is installed by default and will quarantine a simple rust binary and often tell the user they have been infected with a trojan. I know that sounds ridiculous but i spent a lot of time looking into it.
The problem is they have no incentive to not false positive.
Even though GNU/Linux systems don't have these types of restrictions, it would be great to have better sandboxing between desktop apps for a given user. Despite the intentional malware, software exploits and RE bugs exist and would be nice to mitigate with limited scopes and etc. Does Qubes provide better isolation or are there better alternatives?