As a seasoned web developer who has worked on multiple FAANG “.com” domains, I think you’re overstating the impact. Every big web shop already codes for market

As a seasoned web developer who has worked on multiple FAANG “.com” domains, I think you’re overstating the impact. Every big web shop already codes for market share, which means chrome, then hopefully has an iPhone they don’t allow to update to test in older versions of safari (sourcing them from eBay if necessary) to then litter their code with if safariBadVersionWhatevers. Smaller ones test it on their latest updated phone and then throw it over the wall, and call anything non-chrome best effort. To the extent that I’ve seen Firefox, supported it’s because the developers of the site personally use it. Nothing about the safari monoculture on iphones makes people support Firefox because support is 100% a function of market share, and the monoculture actually prevents the Firefox engine from getting a sliver of market share on iOS. The state right now isn’t “people code to web standards because safari forces them to” - its that they spend time % proportional to market %. That means code to chrome and then fix bugs in mobile safari. And even if chrome was wildly successful in getting iPhone users to switch and destroying safari marketshars there, reducing testing on safari, it doesn’t hurt Firefox. Testing on safari doesn’t help catch Firefox bugs because it’s a totally different engine.