I think it will because people keep bringing it up and blatantly telling Rockstar they think they will.
At this point it will become a self fulfilling prophecy.
At minimum it will be $80 like Mario Kart because as some people have pointed out there will probably be a Deluxe edition that will cross that $100 barrier.
it will cost more than that for the "special deluxe early access" aka the regular version followed by the gimped discount version delayed by a week or two for 70-80
They could and it would still be the best selling game ever but I don't think they will, $70 is my guess but Nintendo has opened the door wide open now, only a matter of time until PlayStation, Microsoft and other big publishers do the same for their titles.