1e presented psionics from the very beginning, it provided more than a few monsters with psionic powers that would only matter if there were a psionic PC in the group (as well as a few with psionic blast, as well), the odd magic item that interacted with psionics.
And, while it was unlikely a given character would be psionics, it was similarly unlikely that a given character would have an 18 stat, let alone, say, % STR (never mind 18/00, specifically), quite a lot of magic items were pretty rare according to the tables, too, but that doesn't mean they weren't in the game. 1e was presented as a game you'd play a lot (including rolling up a lot of new characters at 1st level, after the previous one had died, at 1st level), so an expectation that the rarer stuff'd come up, eventually, is pretty fair.
5e hasn't put psionics in print, yet, but it has at least been in the theoretical development pipe-line, just for a really long time - a bit longer than the now-in-print Artificer was, IIRC. Still, seeing the pipe-line is something.
And, if we're being fair (and, I know, why start now), whether you compare it to glacial-pace-of-release 1e, which had psionics from the very first book, or fast-pace of release 4e which had it 2 years in, 5 years is more than both 0 and 2.
5e has taken the longest to get psionics into print.
It's not even close.