Wow you love taking things out of the context they where originally stated in. Five times does not mean anything in comparison to a character whose sales where never high at all. Five times in comparison to where the original of the title had to come back on Sam's third outing in hopes of salvaging what was left of a degraded concept.
The Nova fanbase may not be as strong as some others but just taking a peak back when it was at it's height it's clear that it could have been. The creation of Sam and the handling of him there after ruined that. Which sucks for not only the character but for the small representation he has that could have been represented in a big way. At this point it be better for the potential franchise to move forward with the guy who people proved to have liked and see if he can fix what's left of it. Rich.
Your points about Spiderverse is built on a false premise. What that movie shows is that Miles ,who is different character than Sam, may have a shot. But even in saying that Peter Parker is in the film helping him get a leg up sooooo....*Shrug*
Again the if the MCU does a movie it can go either way. I'm hoping it will be Rich and then Sam can show up later down the road.