Only roughly 10 of the 32 starting QBs are statues (see link) that's 31.25% of the league which means 68.75% of NFL QBs are "mobile" now. Which is exactly the reason we saw so much struggling at QB this year. The game is played much differently than in the 60-80s.
Link: https://www.nbcsports.com/northwest/seahawks/nfl-power-rankings-all-32-starting-qbs-after-2021-nfl-draft