I'm probably alone in this, but WEI is a good thing. Anyone who's run a site knows the headache around bots. Sites that don't care about bots can simply not use WEI. Of course, we know they will use it, because bots are a headache. Millions of engineer hours are wasted yearly on bot nonsense.
With the improvements in AI this was inevitable anyway. Anyone who thinks otherwise is delusional. Reap what you sow and what not.
edit: removing ssl comparison since it's not really my point to begin with
WEI does prevent any customization.
Or by isolating the browser from third party software. Android does not let applications mess with each other. Windows already prevents non-elevated applications from touching elevated applications (i.e. running as administrator).
What makes you think that Windows won't add an "untouchable" mode to executables belonging to "approved" browsers? The kernel is already locked down so you won't be able to bypass it that easily.