This is part of the problem. The numbers of negative bear encounters compared to the numbers of people and bears in the forest are incredibly small.
I suspect the majority of bear spray incidents go unreported since the people spray and the bear runs away. The increase in numbers of encounters over the past several years is almost certainly due to the dramatic increase in the number of hikers in the backcountry over the past decade. Most of the hikers I see are carrying no defense against bears and they somehow almost all make it out of the backcountry alive. But if even a small percentage of those increased numbers are carrying bear spray then you are going to have more spray incidents.
Charging bears are rare but when they do charge they are mostly bluff charging. Usually the bears just stomp and huff before backing away. I have witnessed this personally on several occasions once at a distance of 15ish feet where I surprised a bear eating berries as I came around some thick shrubs.
Human habituated bears can be a threat as can very sick or starving bears. Bears around an animal carcass are one of the bigger conflict situations as they will seek to protect their meal or take it from whoever currently has it. Brown bears with cubs should also be avoided. I have accidentally gotten between a mother black bear and her cubs on several occasions with the mother just silently watching me or showing nervous concern but no aggressive behavior. One shouldnāt act aggressively around a black bear and cubs but getting between them is not the death sentence popular myth would lead people to believe.
Bears in general are focused on fattening up for winter hibernation and almost always seek to avoid conflict since it keeps them from their primary goal. Most negative bear encounters are caused by people doing stupid things like feeding bears (intentionally or unintentionally) or threatening them by getting way too close.
None of the above applies to polar bears. They will consider you a free lunch if they see you.
I am not saying people shouldnāt carry protection. But threat deescalation and conflict avoidance works even better with bears than it does against 2 legged predators. The bears are much more predictable and way less likely to be out looking to harm someone.