Good luck having bunch of lawyers figure out what the impact of a browser "engine" is.
And honestly good luck having regular users care about this, either.
The reason Apple won't have a problem with it is because the whole argument is just in the echo chamber of web developers who want their new shiny.
I don’t remember my parents losing sleep at night because third party ISP couldn’t get the same access to copper lines. Yet we got meaningful regulation of that market.
I think as long as there’s big enough third parties losing money there is hope for change.
Apple monetizes Safari. They sell hardware and subscription services.
Facebook monetizes in part through these browsers. The changes to Safari hurt Facebook revenue.
If Google were to lose android I wonder if they’d also push for more regulation on Apple.
I wish I could just say “Firefox”, but I’m afraid they would be small potatoes in this.