Earlier quoted context omitted.
If that is the case, why are dev salaries in, for example, Dublin so much higher than Berlin (€115,000 vs €86,000 if Levels.fyi is to be believed)? Both are EU capitals with excellent, well-educated workforces.
Because of the additional cost that the employer is imposed on by the state in Germany. I bet that the total cost per employee is pretty close.
The cost is not close when you consider US tech employees who earn almost double what EU and UK employees earn. Corporate taxes in the UK have traditionally been lower than the US and UK companies don't pay for medical insurance. It's simpler and cheaper to launch a startup in the UK compared to the US.
I doubt the situation is much different between US and German or German and Irish companies. It's rare in my experience that companies can explain away salary differences by showing cost differences. Which should shock no one. Most companies seek to minimize labor costs and at best pay close to local market rates. Or even hire in foreign markets to reduce labor costs. If instead they were seeking to share profits you might see the result you're describing.