Here's an updated list of relatively popular phone manufactures and their bootloader unlocking potential.
https://github.com/melontini/bootloader-unlock-wall-of-shame...
https://github.com/melontini/bootloader-unlock-wall-of-shame...
This proves there is no technical difficulty to provide unlock bootloader
No, that's exactly the sort of tactic you'd expect from them.
And it's also partially false, as Gemini works just fine after unlocking/relocking, and all the advanced features (full performance of the cameras, NPU access, secure element) work even on non-Google OS. Things that do not work (mostly wallet) are valid issue, but then again, they work just fine after flashing OEM firmware And relocking The bootloader.
So I can only guess the quality of the contribution is similar with other phone brands.