If you just want to run some Linux software, or do linux development, a modern Chromebook is totally sufficient. The built-in Linux VM is easy to set up and no longer requires voiding your warranty.
Docker, VSCode, et al works great.
It's a very different world than 5+ years ago with crouton, etc.
Fair one if it's improved but it still feels on par with WSL2 for user experience, some people like that I guess. A vanilla linux laptop just seems better imho but I've not played with one for a while, I admit.
WSL2 has significantly worse experience IME. The ChromeOS Linux VM takes like 10 seconds to launch initially, but after that I haven't observed any latency.
Meanwhile, the same dev stack running in WSL2 has noticeable latency e.g. seconds of extra delay launching any containerized Python interpreter (on a powerful Windows desktop workstation, too).
Yes, Chromebooks run coreboot and almost every model has a community coreboot build with a SeaBIOS/EDK (UEFI) payload available. [1]
When you flash that, you lose the ability to boot ChromeOS, but you can install a standard Linux distro on them.
IMHO, Chromebooks are awesome machines. With ChromeOS they have one of the most secure boot chain/data models of anything currently shipping. Unlocked bootloader, vboot by default, all user data is encrypted, and power washing is trivial. Amazing battery life. Also, they're cheap, and guaranteed to run coreboot with a bootloader that can always be unlocked by the user.