With no kids, my wife and I have been traveling in "shoulder season" for decades. We always liked the reduced crowds and often reduced prices that came with it. Temperatures also were milder and pleasant.
I wonder, though, if that has changed enough post-COVID that it really is no longer "a thing". Or maybe, it's popular enough and so many more folks are traveling so that "shoulder season" is the new "high season", and "high season" is now "unbearable season"?
What are you finding in your travels? Are the months leading into and trailing after summer's high travel season starting to fill up and lose the old advantages? Are travel companies (airlines, hotels, tours, cruises, etc) using their new technologies to maximize profits in a way that cost savings are disappearing? Is the new normal 9+ months of high season, and winter, non-holiday months the only "low" times?