No comment on the overall topic, but I have long made a practice of installing into $HOME/Applications instead[1], and it's rare for me to encounter software that cares. A few apps have added popups to explain to beginners "Hey, you're running me from the Downloads folder, uhh, want me to properly move myself to /Applications/?" but that's about it.
The only apps I run from /Applications that aren't part of the OS are the ones that still use "Installers" like Adobe apps, because I assume they spew crap all over anyway. I haven't tried moving those, but I wouldn't be surprised if they deeply cared.
[1] The idea being that I could then migrate more easily by copying the whole home directory, and thus all my apps that didn't require "installation" would come over.
The only apps I run from /Applications that aren't part of the OS are the ones that still use "Installers" like Adobe apps, because I assume they spew crap all over anyway. I haven't tried moving those, but I wouldn't be surprised if they deeply cared.
[1] The idea being that I could then migrate more easily by copying the whole home directory, and thus all my apps that didn't require "installation" would come over.