I watched the original video, and honestly I think the reviewer misspoke when he used the word "innovative." In context, I think he meant that stories of today feel as though they lack the depth that they used to have: as in they don't explore themes, motifs, character arcs, and convey messages as frequently or as well as they used to. The main 616 comics are perfectly serviceable popcorn stories, but feel hollow as compared to stuff like the 911 issue, the silent issue, To Have and To Hold, # 400, Best of Enemies, the Kid Who Collects Spider-man, The Night Gwen Stacy Died, etc. We rarely get that type of weighty heartfelt stuff anymore. So if that's your cup of tea, you're not really going to appreciate what's going on today.
"Innovative" itself could be interpreted many different ways: unique plots and characters, or unique art styles, use of dialogue, pacing, etc. Also does innovative mean innovative for this particular character, the industry as a whole, or the entirety of fiction?
Most of what Ive read of Spider-man has been in hindsight (I started in the mid 2000s) so, if I'm excluding stories prior to then, I suppose the Superior Spider-man run would be the biggest contender. In terms of artwork, I thought the art direction and design of the initial Spider-Gwen run was innovative and was a big part of its appeal.
In a decade or so, we'll be a century into mainstream superhero comics. If you started reading in the mid-2000s, there isn't much that hasn't already been done. If it wasn't done with Spider-man, it was probably done in Batman, Superman, the X-men, etc.
I'm not sure I follow what you mean by Parallel Lives copying To Have and To Hold since Parallel Lives came two decades prior. Unless you mean reading those two stories today without any context?
Parallel Lives was basically just Conway taking all of the subtext from his 1970s work and making it as explicit and in-your-face as possible so there would be no confusion about it.
Conway believed that MJ read like she was always intended to be the main love interest based on Ditko's teasing of the character and Romita's introduction. Thus, he got rid of Gwen and used the tragedy to bring Peter and Mary Jane together. He doubled down on that idea in Parallel Lives by working Mary Jane into Spider-man's origin. He also used Gwen's death in the 70s to show that, behind their contrasting exterior lives, MJ and Peter actually had quite a bit in common in that they had similar character arcs. Parallel Lives was basically Conway making his intentions as blatant as possible.
I agree though that To Have and To Hold is a better written story. It takes a far more subtle approach in explaining why Peter and MJ work as a couple, and tells a more engaging story in its own right without any major retcons. I'd probably put Parallel Lives higher on a required reading list, but To Have and To Hold higher on a Best Of list.