If I don't want to use Windows or MacOS, I can use an alternative operating system. If I don't want to use Google's search engine there are many other alternatives. If I don't want to use a companies webmail solution I can setup my own.
It is very simple to not deal with these tech companies.
You may find it easy, and well done if so.
Every step you have listed there is quite hard, even if you let some through (Apple in my case). Some of the things you are cutting out are very good, and that’s how they get you.
There is still lots of stuff I kinda have to use but I've managed to massively reduce my use of most of this stuff.
Obviously if your job/business relies on using this stuff then you gotta use it. I wouldn't advocate that you put yourself out on the street for the source code freedoms.
What device would you use? How would you find information? It’s all possible, but not straightforward. There is likely a good sci-fi or black mirror plot in here somewhere.