Interesting. I have what appears to be exactly the same bluetooth headset setup (Bose QuietComfort 35s), and use it all day every day while at work.
I have the slightly annoying thing that if I'm in a video conference all normal audio isn't heard (unless I switch the default audio output), but I only get that when actively in a VC. I have never had 'random applications requesting the microphone'.
See for example the pages of complaints about windows forced planned reboot features deemed unavoidable from the hn majority, let alone the common users.
Any one of {Bluetooth SIG, device manufacturer, Microsoft} could have independently fixed the issue. Every one of them should have forseen it. None of them foresaw it and none of them fixed it, and years later it still lingers. Yikes.
Details: Bluetooth headphones with microphones actually show up as 3 sound devices, one high quality output device and a pair of low quality input and output devices. Whenever a microphone is requested, the low quality pair is selected. Output quality goes to shit and any apps that don't get the memo will still send its audio to the high quality output device which has since become an inactive sinkhole. Since many apps request microphone access for non-obvious reasons, the symptoms are that you do something non-audio-related and sound in the rest of the system does some combination of {go to shit, stop working} on a per-app basis. The solution is to disable the low quality input and output devices, which keeps sound output functional and high-quality until Windows Update reverts your settings and sets the stage for the next microphone access to break bluetooth audio again. Ugh.