The only way to accomplish this at scale is to build something that is legit better and let the market decide. Anything else is just principled wishful thinking.
Microsoft Teams "won" entirely because it was given away free with Office. Even though it is acceptable these days, it was horrible when it started. There is no way it could have won without unlimited backing from a bigger force.
You have to see EU trying these things in the same light.
Now we have a US leader who may wake up tomorrow and put 100% tariffs on cloud services to EU corps or have the NSA demand chat logs.