You are right. Either you are using docker very wrong, or docker is not meant for this use case.
You say “getting ubuntu server to fetch it’s updated behind proxy”. You shouldn’t be updating Ubuntu from inside of docker. Instead, the system should be somewhat immutable. You should configure the version you want to use as part of the Docker file.
Same with python and keys. You likely want to install python dependencies in the Dockerfile, so that you can install them once and it becomes bundled into the container image. Then you don’t need to use pip behind the proxy.
Honest question: could some of Netflix’s enshittification be because of the media industry, and not their fault? The fragmentation of streaming was the opposite of what they wanted. So maybe his point is that it’s impossible to compete because the industry is so powerful and greedy that they couldn’t hold onto their monopoly. Spotify has been able to hold onto theirs because record labels hold less power and don’t want to get into the streaming business.