IMO, the gaps of note are not between specific franchises, but between franchises within the genre. Superman IV wasn't out of sight all that long before Burton's Batman revived interest in superhero films. The X-franchise hit only a few years after Batman & Robin.
So, to the OP, I don't think we're going to have to wait all that long. In addition to the genre being sleepy-rather-than-dead, Wonder Woman seems to get a friendlier reaction than the likes of Captain Marvel.