Since I can only sort 1 stat at a time I just checked the things you listed with only 1 stipulation. Here are the ratings that you listed as being inflated on the default rosters:
5. Default: 17 HBs with >85 CAR.
2020: 12 HBs with >85 CAR.
6. Default: 120 HBs with >90 SPD.
2020: 127 HBs with >90 SPD.
8. Default: 58 QBs with >85 THA.
2020: 118 QBs with >85 THA.
Of those, the HBs with high CAR is actually a little higher on default rosters, but on par with how it looks in 2020.
There are slightly more HBs with 91+ SPD in 2020 than on default rosters, but again, they're on par.
However there are WAY more accurate QBs in 2020 than on the default rosters. So, for at least these 3 ratings that you care about, the default rosters aren't inflated compared to rosters made up of generated recruits and the generated rosters are more inflated than the default rosters.