First, get rid of whatng web engines and google/apple apps... wait.... mmmmmh... how many devs fully subsidized to dev and maintain some "replacement"?

On this matter, the only way out, technically simple protocols but doing a good enough job allowing a small team of average devs or even an individual average dev to develop and maintain an alternative software with a reasonable amount of effort. That with some hardcore regulations to allow them to exist. Remember that nearly 100% of the only services were fine with the classic web, aka noscript/basic (x)html web (and if you add only the <video> and <audio> elements you are getting dangerously closer to those 100%)

Don't forget, you cannot compet on economic grounds and international finance, their thousands of billions of $ will wreck you. And china is on the other side of the spectrum. You will end-up crushed on both sides.

And first thing first: some high performance EU silicon (design and manufacturing)? But we all know the state-of-the-art silicon tech is an international effort.

defence grade effort at EU scale... oooof!