The EU regulation doesn't say "USB-C", but "industry standard charging port" or something. What's industry standard is an executive decision of the EU commission, unless the USB-IF does something tremendously stupid the commission is just going to rubber-stamp any new standard they come up with.
The EU didn't event want to legislate in the first place and would've preferred for manufacturers to get together and just be sensible, but, well, Apple. The only hold-out.