Why do you think Apple blocks all web browsers from using their own browser engines and forces all browsers on iOS to use Safari? And no, the answers do not include "because privacy" or "because power usage".

People should be free to use other browsers and accept higher power usage, or "privacy risk" without Apple forcing their own browser engine, which limits functionality of all web browsers on iOS.

What Microsoft did by bundling IE with windows was far less egregious. Could you imagine if Microsoft forced all browsers on Windows to use IE as a webview? Holly shit people would be rightly pissed.

Apple does this specifically to prevent competition from web applications so that developers have to use Apple's app store, where Apple can charge the developer/customer money. It's spelled out in the DOJ lawsuit against Apple.

https://www.justice.gov/archives/opa/media/1344546/dl?inline