The regulation doesn't mean batteries have to be made swappable with just bare hands. Common tools and some simple, easily undoable gluing is still acceptable. It gets a battery replacement from a process that risks breaking glass parts, overheating components etc.. to something that can be done by a moderately skilled person with a moderately well stocked toolbox in an afternoon.
Isn’t that the case already for most devices? I can pay £80 and have a guy show up in a van and replace the battery in my iPhone in his van in 30 minutes or so.