There may be a very few players in no wheelchair classifications that may be able to use dumb rackets .
But dumb rackets make no sense at all for wheelchair players, I am not saying this as a disrespect to thier disability but it is the same as to why most humans para or non-para have a different or weaker backhand as biomechancial nature of human physiology as applie dto any racket sport bit all the more so for table tennis.
In fact children or older adults (especially those withj neuro cognitive disorders) should not starting in the sport using dumb rackets .
It is just that it may be that much harder for a wheelchair player to use a dumb racket .