I don’t know of course, but I believe - like with many other things - the FP1 GPS problem was a mediatek problem and the FP2 will be mediatek-free AFAIK.
This could have to do with the fact that FP1 was built on a pre-existing Chinese Phone. Fairphone was building the second model themselves and I am confident that they made sure that it will be compatible with standard European headphones.
I like the idea and added it to the modules wishlist