Obviously none in 5E, but they were common in 2E and 4E games I played and ran, and I saw several in 3E. I've seen way more Psionic types than, say, Druids or Barbarians, heck, even than single-class Rangers.
I agree that the wizards by another name approach is weaksauce. The non-wizard style Psionics users always got more play (including the original, Roguish Psionicist).
Same sort of experience. Psions were more popular than druids, sorcerers, bards...they saw a lot of traction at the table.