@shmerl has a valid point here and I fully agree with it.
Some people might find it useful to have extfat even as I do not find it useful. I would not mind if had been there in the beginning, as a "baked-in" cost of the original design.

However, when given as an extra perk, as an option to be included or not then I want to voice my opinion on whether it is useful, or whether some another goal could be reached instead of it;

I can think lots of HW related goals that would be more useful; Qi charging, better environment sealing, USB-C connector, etc etc.

As for SW related goals; well, without knowing what SFOS2 includes it is difficult to formulate an opinion on it.
However, I'd rather see HW additions than SW or Licensing additions for the simple reason that the latter can always be updated later but the former is there to stay when the device has been made.