They have already been moving the DVC point chart in that direction, but really -- DVC is a small percentage of total WDW guests.
At most, DVC is 10,000 - 15,000 guests at any given time. And occupancy at DVC is consistently high. Not like occupancy is 50% during the summer and 95% during Food and Wine.
So the difference in DVC guests at the park in October vs July, is likely no more than a couple thousand people, total, at most.
The issue is simply that as travel has become more globalized (pre-Covid), vacation demand has become more complicated than the school calendar.
Put aside that it's a theme park, who would want to go to Florida swamp in the middle of summer? Options for family vacations have grown, where everyone isn't clamoring to swelter in Florida summer heat. Families are taking more cruises, more international travel, etc, than decades ago. October is indeed a much more desirable time to be in Florida.