It's a good question because maintaining a modern web browser is a complicated and expensive project, which any potential buyer would have to sustain financially somehow. Chrome without the integrated ad service business would probably be highly unprofitable - so why would any business take it on?

The only real answer I can come up with is pretty ugly: data mining. Lots of services are dependent on Chrome that can't just move to a new platform on short notice. Chrome is not just the web browser, it's also the web engine for most mobile apps (a lot of apps are just stripped-down Chrome with a hard-coded server target).

Chrome has basically sucked all the air out of the room for other browser projects, so maybe taking it away from Google will create some space for new projects to grow... but it's hard to see any of them becoming well-developed and trustworthy for things like health data, government services, financial transactions &etc anytime soon.