I like the Custom Tabs feature. It avoids security concerns with web views and the back button works how you'd expect it to within a single app. If you want to open the page in your browser there is a button in its menu to open it in Chrome (or whatever your browser is) instead.
Meanwhile Google built the Custom Tabs feature[1] to push Android devs into the exact opposite direction: Even when the app just wants to open an unrelated page (e.g. from a user-provided link), its now encouraged to open the page in a "custom tab" instead of the default browser - with the explicit goal of keeping the user from leaving the app because precious precious engagement etc...
Naturally, there is no systemwide setting for users to turn it off, you have to find the setting for each app separately (or rather hope it has a setting at all).
[1] https://android-developers.googleblog.com/2023/02/bringing-b...