That sounds like bullshit as such clauses are nonexistent and nonenforceable in Germany

Edit: I’ve seen they’ve put this bullshit in. It does make me wonder if they’ve used ChatGPT to generate this. I’m not a lawyer and this is not legal advice but I would be very surprised if this would hold up in court. There is a reason that no big company or like nearly all companies don’t have this in their ToS with end customers as it would probably get thrown out in court immediately

Some Law firms also write that this is not possible with end customers

https://cenacom.com/zwingende-schlichtungs-und-mediationsklauseln-in-agb-unzulaessig/