If we're not taking into consideration the context of the ask, we're not going to be able to understand the nuances here.I understand but they don't know what my 10 is. I had no idea what pain could be till I had kidney stones and even then I have no idea how that compares to a war veteran getting severely injured in the battlefield or a burn victim. I've sat and watched people in the hospital say 10 while they're sitting in their bed me watching TV. When my wife was dying she was screaming in pain and we had to hold her down and she would say an eight. I'm just trying to say that self reporting pain is dubious and comparing is of little value. If someone says they are suffering then they are suffering and we need to try to help them.
When receiving medical care (such as the example you gave, or in ER triaging), there is an incentive to overstate your pain level because that's how you get attention faster. Doctors and nurses know this, and don't only look at your self-reported data.
In the context of scientific studies, that incentive doesn't exist.
For tinnitus in particular, scientific studies often do measure volume (through stimulus matching and adjustment for PTA losses, there's also MML/min masking level - many of us have gone through that with an audiologist). There are many studies that study correlation between loudness and distress (look for them on PubMed, example.
We can keep saying that loudness doesn't matter, and that it's how we deal with the sound that matters, but the science disagrees. It also perpetuates victim blaming ("you're not positive enough! that's what your problem is!") and doesn't encourage finding a real cure (since it really is all in your head, you're just not trying hard enough to get better).