(It's important to note that this thread isn't about an individual fan's thoughts on the subject as there are people who don't care about MJ and would prefer Peter with someone else. This is about the collective fandom as a whole.)
Based on an exchange I had elsewhere with people about Spider-Man, the discussion turned to the subject of the current run. Someone said that after Spencer reconciled Peter and MJ, that there was no putting that genie back in the bottle. That even if the current run were better received, there would still be an extremely pervasive negativity around it. And that this was with Black Cat serving as the potential love interest for this run. This person then said to imagine if the potential love interest were a new character. Someone else chimed in that fans don't have to imagine that, fans saw what happened with Carlie.
(I should note that these folks aren't huge Peter x MJ shippers or anything like that.)
It got me thinking. MJ has been the fan favorite love interest since the days Stan Lee and John Romita Sr. were on the title. Their intended love interest, Gwen Stacy, never was a hit with fans in the way MJ was. The first regular writer of Amazing Spider-Man following Stan Lee, Gerry Conway, was a huge fan of the Peter x MJ pairing.
At this point, the Spider-Man franchise is over 60 years old. It's truly difficult to go against such things at this point, if not impossible. So I ask the question. Do you think fans would accept anyone except MJ as THE love interest for Peter?