I'm skeptical that a change in saddle would make a huge difference for the average rider. I personally find that my comfort on the road bike correlates to how hard I'm working - active group rides I'm fine; noodling around with family on the same bike is a lot less comfortable. The only difference I can see is that I'm putting way more weight on the peddles in the first case compared to the latter.

I imagine your average rider is probably a lot closer to noodling around than a group ride.

Both you and the parent commenter are correct; A saddle that matches your personal anatomy will make a tremendous difference for all riding conditions, and the amount of times you vary your position on the bike will alleviate discomfort by allowing blood to flow naturally as your weight shifts. More intense riding conditions necessitate moving around on the saddle more often.

Additionally, if you simply ride your bike more often your groin and siting bones will feel more comfortable by acclimating to the pressure and movement. It's helpful to wear appropriate clothing in the areas that contact the saddle as well, such as a chamois liner, to reduce friction and add an appropriate amount of cushion.

I would also be uncomfortable on a road bike when not exerting myself. That being said, there are good reasons why bikes come in different shapes for different use cases. Casual riding can be very comfortable with a more suitable frame and configuration.

The one-bike-that-does-it-all (aka "quiver-killer") is an elusive beast in the cycling community, it's no surprise your road bike doesn't fit the bill. The style most people end up settling on is something along the lines of a light-ish steel touring frame, with reasonable slack and tire clearance, equipped with a Brooks saddle and handlebars with multiple hand positions.