I, too, think you should accept very update. There are just too many things you could miss, like new features. We got pano like that. Those that refused to update, the very few, didn't get pano and who knows what other improvements or protections, better running equipment.
I think you might be a little off on your estimate of how many people stay on old firmware. The author of those videos that I posted has several videos with over 50k views detailing how to downgrade. That's just one channel. There are many others with lots of views out there. I'm not saying that everyone who watches ends up downgrading, but there are many people who do so for various reasons.
Now Medflight, some of those reasons people may choose to downgrade are:
1. Wanting to use a proven version of firmware. Firmware released 2 days ago is not proven, and has a higher chance of having bugs. Firmware that people have been using for over a year has proven itself.
2. Restriction removal. Some people don't want to be dictated in how they do things. If I'm flying up a mountain, and staying within the rules, it's a PITA for software to decide I shouldn't go any higher. I take that restriction off.
3. Modifications. Some people are tinkerers. They like to mess with things and push the limits. If they want their Mavic to go 50mph instead of 40, they can do that with downgraded firmware. Who cares as long as they aren't putting anyone in danger. Or maybe they want to remove those pesky wind warnings. Or maybe they want the auto takeoff height to be higher. Plenty of reasons to want to mod the flight parameters.
4. Removing DJI phone home. Some people prefer not to have every action of their property being reported to others. Doesnt mean they are hiding anything, some people just don't like others "looking over their back" constantly. I don't want the dealership sticking a tracker in my car. It's mine, if I want you to track me, that should be my choice.
Even if you want the newest features such as pano mode, you can pick and choose which modules within the firmware to update. All of this is very simple. There are videos detailing how to do everything. As long as you can follow simple instructions, the downgrading process is a breeze. Even mixing modules is super easy. Not to mention there is a wonderful community willing to help you if you need it.
There are also reasons to use the latest firmware, but I won't cover that since several already have. Too many people say there is no reason to not upgrade, just because that is what they do. "Thats what I do and so should everyone else, because its right, because thats what I do." lol
Have fun and safe flights!