It's a common reason given by people who dislike psionics in D&D, but, as other people have pointed out upthread, D&D has a tradition of science-fictional sounding magic spells: telekinesis, teleport, clairvoyance, clone, etc.Maybe the issue is the serial numbers aren't very well filed off when it comes to psionics?
Why doesn't nomenclature matter with them? You could easily call them 'hand of the spirits', 'thousand league step', 'farseeing', and 'conjure scary double whose probably going to turn on me'.
I guess the answer is, as usual, it's just a matter of taste, not reason.
Personally, I think D&D-style fantasy is defined by rampart genre-blending and gleeful historical inaccuracy. I enjoy D&D settings which embrace their wild anachronisms and use lots of contemporary language --I did things like name a press gang the 'Fort Ormand Asymmetric Recruitment Squad'.