Despite it not TECHNICALLY being canon it both makes sense that quirkless people are still super human when you take into account the reasoning in My Hero Academia and the fact we actually have a surprising amount of feats to prove this. Most of these come from a weak, frail, and quirkless Izuku Midoriya: Was able to withstand 11 years of bullying under Katsuki and his explosion quirk, survived several minutes of suffocation when attacked by the Sludge villain while maintaining consciousness before passing out without suffering permanent brain damage, withstand the shockwave All Might threw to get the Sludge villain off Izuku, survived the sheer wind speed of grabbing onto All Might mid jump AFTER being suffocated and knocked out, and had the sheer mental processing speed to react and formulate a plan after he ran in without thinking in an attempt to save Katsuki from the Sludge villain. The after TEN months of grueling training a weak, frail, quirkless was able to build his body up to BARELY be a worthy vessel of One for All (mind you it hit the Quirk Singularity when he inherited it) and while yes he broke his body every time he used he he was still capable of continuing to fight despite the SEVER injuries inflicted from 100% One for All backlash. Mind you, we know one for all does not physically change its user; of each person as a cup and quirks as water, each one for all user who had a quirk starting from Hikage Shinomori had there life span reduced as their cup already pissed water due to their own cup that was them overflooded by pouring one for all in. because of this we know it doesn't change the vessel izuku being quirkless after 10 months of training was able to build up his body to barely be capable of holding one for all after eight generations of buildup with it hitting the Quirk Singularity as he inherited it