Theoretically, yes, they could do that with the electronic fuses to prevent firmware from booting, as the Tegra on Switch 2 likely retains the same system. However, they probably wouldn’t do it mostly because it would deprive them of boards for refurbished consoles, if not whole units they can go and turn into systems they can send back from the repair centre. Besides, all they really need to do with any potential brick is to stop most people from using the device and to give up. I can’t be entirely sure since I don’t know the internals that well, but it wouldn’t make sense for them to do an irrecoverable brick.

Thanks for letting me know about the eFuses though in the Switch 1 chip, wasn’t aware of those before.