I just finished my second year as a fifth grade teacher, so I have a lot of experience with ten year olds. I am confident a majority of my students would be able to install an alternative web browser if they needed to, and a majority of the remainder would ask a friend to do it.

To give you an example of the workarounds kids will find: Youtube was blocked on school laptops, so the kids all started embedding Youtube videos inside of Google Sheets in order to watch stuff. This isn't, like, something a few savvy kids did, it was a widespread and common practice.

And, in my opinion, a healthy thing for the kids to learn and do.