The only thing that has changed since camera and microphone access was allowed is that Apple now considers web apps to cut into their app store business, so they are unwilling to let any new APIs get approved that would make a web app as capable as a native app. This includes WebBluetooth and other APIs.
Apple is also getting sued by the DOJ for exactly this type of shady business practice.
And I don't really think what Firefox says is relevant, they are so cash-strapped I would not doubt that Apple pays them to have a negative opinion about new web APIs just so people like you can say "Firefox doesn't want it either".
The truth is there is no good reason to block WebUSB and WebBluetooth from becoming standards.