It is called a rubber o-ring.
That's how other companies have been making water-tight compartments for batteries and other things for literally decades now. But all of a sudden, Apple wants to pretend this is some unsolvable problem. For fucks sakes stop acting like this is some insane ask, goddamn it.
No other government body is as consumer-friendly as the EU, so I really hope this bill passes and forces Apple to comply. I am so sick of the bullshit from these megacorporations who are so big they just don't give a flying fuck about what consumers want. And on the flipside, there are going to be a million Apple apologists who will side with Apple on this topic. Those bootlickers only make things worse for everyone.