If the security benefits of a pixel is less important then the fact Google made it then GOS is simply not meant for you.
Its silly people complain about it being only compatible for pixels but never seem to blame other android brands for making significantly less secure phones. The responsibility should be put on phone makers to create secure phones that meet GOS requirements, not to expect GOS to make a less secure OS.
The whole AOSP environment is very Google centric so its pretty weird to think because your not buying a pixel that you are somehow avoiding Google.