I think it shouldn’t be a problem to not add a Google account.
Just know that Google still collects your data.
At some point FP will probably release Open OS for the FP3 too, which is Android without Google. This will collect less data.
See this discussion:
There will most likely also be alternative OSes ported by the community at some point. You’ll be able to find them in the oslist.
I tried to install Lineage OS on a supported Samsung device and failed. Will it be more simple to install alternative Firmware on FP3? Can you compare?
In my experience - I installed lineage OS on 5 different devices (LG, Samsung, BQ, Motorola and FP2) - FP2 and BQ were the smoothest installations … pretty straight forward and no problems with unlocking the bootloader and flashing a custom recovery