I agree with a lot of your comments, but just FYI, you can do a couple of those things:

> (I can't even compile FOSS apps on my own without owning a mac + 100$/year dev licence - this is a real shit show for me!)

You do need a Mac, but you can build FOSS apps and deploy them to your own iPhone, iPad, or Apple TV with a free developer account. You only need the paid license to distribute them to others.

> Finally I have a device that could replace things like a Wacom Tablet connected to your computer but that opportunity was missed.

There have been apps that support this for a while, but this is now a built-in iOS/macOS feature called "Sidecar".