I've recently played a bit with a Chromebook I have for work, best I can describe it is as "ok". It's kind of fun to be able to write emails, or journal/blog in Google Docs. I really can't see how I would recommend it to anybody really with just that ability. Even non-tech people like to download the occasional program, and not everything is on the web. The Chromebook is able to run Android apps which makes it slightly more useable (Looks like ChromeOS Flex cannot?).
The ability to run Crostini makes it more developer friendly. I was able to set up Android Studio, Python, Gcc, and it's a fairly decent on-the-go dev machine... I don't live such a nomadic lifestyle, but I can see it being pretty fun if you do.