I've been running ad blockers for 15 years now at least, but I seem to recall really annoying pop-ups being a part of Internet advertising too, and they happen more than once per boot.
It's true that in normal use you don't reboot a Chromebook that often, and developer mode offers other advantages as well. And apparently it is possible to "neuter" the screen https://web.archive.org/web/20170711043202/https://johnlewis.... Probably the only real solution long-term...