Samsung is also a safe bet afaik, or Fairphone of course.
For manufacturers where you need to apply for an unlock code, do it within the legal return window of the device (minimum 14 days in the EU (or EEA?) for online purchases), so then that's also a safe bet. Don't need to use the code straight away, though I'd recommend it as it typically (as an extra hurdle¹) wipes the device and you don't want to be doing that once all your data is on there
¹ user safety security blah blah yeah. If it were about my privacy, it could show the same consent prompt as it does for uploading my pictures and live location and rest of my life to a megacorp. If anything, that decision should have an unlock code you need to apply for and supply on a command line to avoid making a mistake in haste
If you can enable root access depends on the boot loader though, which is a different story. If you want to be safe, get a Pixel.