Operating system and CPU architecture are useful for sites to serve the correct binaries when a user is downloading an application.
Barely. You could trim down the data to incredibly low granularity (“OS: Windows”, “CPU: Intel Desktop”) and you’d still get the exact same binary as 99% of the people 99% of the time, anyway.
No. It should be made available with a permission, because not every site out there is going to offer you to download binaries. 1% of the web “”“requiring”“” this does not justify 99% of the web being able to violate that privacy.