Really?
Most if not all EU work permits, especially highly-qualified ones are tied to an employer for at least the first 2+ years. If you get fired you have up to 3 months to find another employer who is willing to take over your residence permit.
Yes, you have three months to find a new job if you're fired, but it's Europe, you most likely got at least a 3 month notice as well.
[1]: https://www.udi.no/en/answer-pages/answers-skilled-worker/#l...
Also, it is definitely not just a formality to change employers. For example, on a blue card the new employer must prove to the ministry that they couldn’t find anyone local or EU to fill this position aka “Labour Market Test”. The position needs to be registered in a special gov database to prove that, etc, etc.