one thing I'm coming to conclude is that there are some geographic and use-case issues at play with that.
When I look at the used kayak market near me, they are largely sit-on. Assuming there's no
Survivorshp Bias here (e.g. people are selling sit-ons and keeping sit-ins), that tells me that sit-on is more popular in this region. Again, could be a lot of factors, but I believe that's because sit-on is more applicable to our area.
One thing I've noticed in the various comparison videos I've watched, they'll talk about sit-on and getting "swamped", and how you and your gear get less wet, etc. but in the very next breath they often talk about how bad it is to get truly SWAMPED as in water inside the cockpit and how you need inflatable bags in the interior to keep from sinking in that instance... or you just get a sit-on.
If I *do* wind up out in boat traffic (or god forbid the cursed jet ski pack) getting swamped, and even potentially capsizing, is a real concern. I've paddle-boarded in the Intracoastal on weekends and weekdays and weekends are no joke but even weekdays can have some challenges.