There’s a funny history where the original iPhone apps could only be web apps as there was no SDK! See history section at https://en.wikipedia.org/wiki/IOS_SDK
But if you're not inclined to educated yourself via the tremendous resource I shared, I suppose you could look at
https://wpt.fyi to see how far behind safari lags in supporting features.
There's also the fact that a proof of concept port of Microsoft edge to IOS significantly outperformed safari.
https://www.theregister.com/software/2026/06/17/apples-webki...
Chrome is also not the only chromium browser. There's also Vivaldi, brave etc, which make up for some of the ad-related shortcomings of Chrome. I happily use Vivaldi.