https://www.youtube.com/watch?v=zIJavqEzEIw (sources in video description)

If your phone isn't manually approved, its assumed your phone doesn't support 4g/5g, therefore, blocked.

4G/5G phones have already been blocked

Fairphone isn't certified in Australia, Pinephone also isn't, nor Librem 5.

Custom ROMs on an approved phone might work for now, but they could potentially start verifying OS in the future if the autocratization trend continues. Also, manufacturers could starts start locking the bootloader.

The best realistic way forward is have two devices, one is the "normie" phone, the other is your own pocket PC running a Libre OS.