in a hypothetical spy browser maybe :) not in any of the modern browser engines like Gecko/Firefox
just be responsible and use Safari if you want the status quo or use a trusted browser engine like from a big company like Firefox/Edge/Chrome
do not be fooled, you people use web capabilities including service workers on websites in all OS, you even did it with Safari on iOS
if iOS had some vulnerability vs. android, windows, linux, mac that made this possible in other browser engines than webkit then Apple has to make the changes
you really think it is an effort if every other OS does this, including macOS?
and if with more information you see Apple tried something fishy here, do not forget like most LLMs most of the prompts in the past... never trust Apple again in this regard!
but you can use other browser engines in macOS (where no app store revenue originates) and Apple never had a problem implementing it and never fear mongered... this should be some kind of implicit proof
but of course Apple will have to prove this and they will fail to do so... they are just pushing the boundaries