> Introducing this nonsense in the EU means that it will be really hard for either side to drop it, since realistically both sides would have to negotiate to drop it together. That's harder than for the US to drop it now, unilaterally.

In theory, yes. In practice, no. The US had no incentive to drop it, so they wouldn't do it (they could have done it a long time ago if they wanted). Now, they have an incentive to think about it and talk to the EU about a treaty which drops it for both sides.