The display only changes samplerate when using ASIO. Not when using the default windows audio. ASIO bypasses windows volume control/sample control.
Yes, but WASAPI Exclusive does the same. But
you do not use WASAPI Exclusive (as sample rate do not change), you lose a lot of quality.
WASAPI Shared is the best option if you want to share sounds, but
your application may not use, it will default to Direct Sound, which is most very likely and the worst option for SQ.
The last two access methods involve system mixer and asynchronous sample rate conversion required to synchronise frequency and sampling time-point of two or more sources. In Windows calculations are in integer 32-bit which insufficient even for CD sound quality.
If you use Foobar 2000, you can select WASAPI Exclusive or ASiO to bypass system mixer, still there is a volume control available. It is done properly with 32-bit floating point without losing SQ.
My setup is as follows. Use integrated sound device as a default sound device, so Windows sounds are mixed with Websites / YouTube / games, etc. Play quality music on the external DAC through exclusive access in Foobar (WASAPI Exclusive or ASIO).
Some browsers (Chrome? With extension?) allow to select WASAPI Exclusive acces, they will have to handle volume control internally, it may be as good as in Foobar.
If you really need mixing sounds, then Windows is not for you, use MAC or Linux and configure it properly. Long story, end of story...
I see Opera GX has separate settings, it may be WASAPI Exclusive option available, right?