That'll be nice, but think about Siemens: they are totally depending on Microsoft. Should I mention governments as well? EU can invest heavily in well established software companies like Canonical (UK based, creator of Ubuntu) which had their own OS for mobile (Ubuntu Touch).
That's just article about software. Software is easy replaceable and relativly low cost compared to hardware. And who needs software if you don't have hardware to run it.
Europe is lacking semiconductor companies after almost all died. The last one are NXP and Infineon but can't compare them to TSMC Intel or Samsung. ARM is just a documentation and licensing company. TSMC foundry in Dresden is planned for 2027 and it's at most 22nm process for cars. If China starts with Taiwan only country capable to go lower than 5nm is USA and maybe Samsung in Korea right now.
The MS lobby is too strong. Many years and many countries tried to get away to linux and many ended up going back because of lobbying or just because it's simpler to pay millions to a single place.
People looked at me wide-eyed when I said "I hope the US votes for Trump" and explained he would finally force the world to decouple from that anti-democratic oligarchy. But they were too addicted to USAian products to listen. When such articles come around, my glee increases.
Weeeelll, we are not quite there yet. DDOS protection for example, only proper company in the EU is Myra, but they cost 10k/month minimum.
Other places are trying but its rough around the edges. For example hetzner does not have all products in terraform, some of their IPs are on blocklists and they don't care, etc.
The problem for large institutions is that they very often have specialized software relying on some American software or being American themself. More often then not that means converting large amounts of data from a propietary format into something useable by another software. The company selling the original software obviously does not want that to happen at all. Also both programs work in different ways, so data might have to be split in non obvious ways.
Then you need to retrain the workforce to use the new software, which probably does not work properly to begin with.
There are also often dependencies. Like Microsoft Office Add-Ins from third party vendors. They will not like going to Libre Office and it is likely not easy either.
Not saying it is impossible, but a transition takes years and is going to lead to some serious problems.
This legacy type software doesn't stop working over night, and while the move to cloud services is more worrying in that regard, this problem is mostly a legal one and the EU could easily change its laws if it would see a need. In fact recent EU legislation explicitly allows suspending patent and copyright protections if foreign software vendors are trying to weaponize this.
At least on end user devices, It's not easy at all to move completely to non-US operating systems. Quite a few places tried and failed to move to Linux.
The critical parts of Android are open source. Many Chinese vendors have versions for the Chinese market that do not depend on any US non-foss software components and the EU could easily do the same. Development would probably slow down, but a smartphone from 5 years ago (with security patches) is not really worse than a brand new one.
The failure of bureocracies to move to Linux is and was organisational and political, not technical.
I am not saying that US software and services are not the most convenient. That is why they dominate the EU market of course, but they are not essential and there is no technical or legal (patents) reason why they they couldn't be substituted quite easily.
Anyways, it is largely a political choice of the EU to import these services, as the US has little else to offer and as good allies (in the past) we found ways to make it work despite the glaring economic imbalance of the US economy.