You are very rare. Most people are not like you.

Apple tried this with iOS 2 and 3. Minor versions cost users roughly 5-10 USD per update.

Therefore many users did not install the latest OS on their devices. The cost, although small, was a barrier for many people.

Apple quickly pivoted and now all software updates are free of charge to all supported devices.

If Mozilla starts charging for Firefox, I predict either people stick with the oldest version that is free, or stop using Firefox and use a fork that maintains its free (in cost) license. Or maybe only 2% of users convert to a paid version of Firefox.

I don’t disagree with your point — however apple only charged for the early iOS updates on the iPod touch. And they only did it to comply with the Sarbanes-Oxley Act — which required that if you upgraded a device not on a subscription, you had to charge.

They stopped doing it after they lobbied congress to change the law.

https://www.macworld.com/article/189247/ipodtouch-3.html

Honsetly, pay-what-you-want-if-you-can would work well. Just make a button appear once in a while (that you can permanently turn off in about:config).

If firefox asked me once a month "Enjoying the entire internet? Is it worth $1 to you?" I'd press the button often.

OS updates are not comparable.

Apple charging for updates is idiotic because as a user I don’t have a choice to go use a different OS.

You do have a choice, just keep using the OS version you have. Just like using the an older Firefox version.

Adding security updates and new features costs time and money.

If Apple delivers a defective device to the customer, I see no reason why they shouldn't be fixing it using the money the customer originally paid. A security vulnerability may eventually leave a device completely unusable.

The point is that with browsers there's also the option of using an entire different one, not just keeping an older version of the same browser.

Apple seems to have made the economics work out well with devices alone.

You don’t even have to touch their services revenue to consider ongoing iOS development a significantly successful return on their investment.

There are a couple of problems with this argument. One is that with a device (especially a premium one) the cost of support for a reasonable lifetime is considered baked into the price. The other is that security updates imply a security issue, meaning the company sold you an insecure, i.e. defective device in the first place.

What stops you? Are you not satisfied with the ones on offer? Is there a compatability issue that's a show-stopper?

What paid browsers are on offer with good technology? The only ones I'm aware of are still chromium based or I think mac only, so that's a pretty bad feature set.