I don’t think I’d expect that from the EU, though as the US has decided to place tariffs on Airbus, then you never know. China and the Russia were the two I considered possible. It would be an interesting path to take, and it’s not a petulantly applied tariff, but rather could be argued to be a path to greater safety, with the grandfathering having been a mistake. It would destroy the 737‘s worldwide market, possibly affect it’s passenger appeal, and also make operations for many airlines sufficiently difficult that it would make them move to alternatives.
Back in the mid 80s, Boeing gave us the 757 and 767. Two extremely good aircraft, that had long legs, covered a range of passenger loadings, and were on the same endorsement. Now they have a cramped, single aisle, aircraft that is grounded.