FYI. We make chambering reamers for most calibers, so I checked sales for the first 8 months of last year compared to the same period this year. Sales of finishers last year were (67); this year (108). I'd say it's still "peaking".
They are just as loud out in the woods as they are sitting at the bench. The difference is like recoil. Your adrenaline is higher so you don't notice it. Wearing hearing protection is not a bad idea as long as you can hear what's going on around you.
I can't open your post! However using them extensively and also selling brakes the answer is that they never change. Rudely loud no matter where you use them, nor your firing position! But they serve the purpose for which they are designed....RECOIL REDUCTION. I have a new model that has a shroud around the brake helping a great deal to redirect the sound more forward