In Europe you have these barriers to removing an employee that make even the most basic of business interactions 10x more complicated.
There are ways to fire people you really don't want in your company, however, it's just a matter of how expensive it will be. The typical Danish outcome of wrongful firing is 1-2 years worth of pay, which is (as I understand it) much lower than the outcome of similar American law-suits. In Europe, this is mostly handled by due diligence, where companies enter agreements with an unwanted worker, giving them 1-2 years of pay to fire them legally. But typically this doesn't happen, because why would you want to fire someone with no valid reason?
Firing someone for not responding to a single e-mail is insane.
One of the advantages to running a company in Europe compared to America is that many European countries are designed to make it relatively "easy" to fire people. This is because we have really good social security networks. In Denmark we have something called a "dagpenge" system, which is a type of unemployment system where you pay some tax-deductible money to be part of an "a-kasse" that will then pay you a healthy sum for two years after you lose a job. The sum isn't quite "programmer level salary" in Denmark, but many companies tend to deal with this by offering 80-100% insurances for those two years through either unions, pension-fonds or private security. In the public sector the unions tend to do the same thing.
I think you may be confusing our overall workers rights with company to employee relationships. Because it's true that countries like France sees some massive worker strikes once in a while, but these have more to do with the government vs workers than anything and typically have to do with how long a work week, how early you can go on pension, how long the social security period should be.
It's true that more people are now putting actions behind their words, and leaving Twitter for the Fediverse because of the new leadership at Twitter, but this seem to be only partly because of the right-wing turn and much more because of the instability showing just how insane it is for the world to let a social media platform be moderated by the whims of a billionaire.
I frankly think Trump is right to stay on Truth. Because what happens when Elon eventually loses interest in Twitter and sells it to someone else? That is the strength of the Fediverse to be honest. You get to operate your own servers that are part of the larger whole. This would let journalists, politicians and NGOs run, and more importantly moderate, their own "Twitter" that is still part of the larger whole. Here in Denmark it would allow our government agencies to operate a "Twitter" where all our elected officials could have an account and not have to rely on an American tech company to moderate their feeds, or risk being banned for violating American laws. Yes, the consequence will very likely be that ultra right-wing networks will be largely isolated, but that's still free speech.