PewPewScience has a very thorough examination of the performance of suppressors they've tested with .300 Blackout (I love graphics and other pictures). Other reviews only offer me words like "quiet" or "very quiet", but have no numbers to back that up... so who else has published real life numbers I can actually compare in order to make an informed decision on something that's going to set me back $1,000 or so? Most of us don't have that in our back pocket on a daily basis. As an engineer, I fully understand that acoustics is science, but it's not "rocket brain-surgery-quality science".
So, I think you answered your question. Full disclosure, we are a corporate sponsor for Pew Science, so we believe that Jay does the best work in the business to present the data objectively. Who else has objective numbers? I am not aware of anyone else. Some manufacturers publish numbers and compare their can to another can, but you have to at least question the data. Maybe it is correct, maybe it is not correct, maybe it is correct, but they cheery-picked which data to present. Some manufacturers do a pretty good job with numbers. Others, meh.
In your last sentence, I agree that the science of suppressor testing can get too complex. To many, the test is "How does this can perform for me in the field, using my gun the way I shoot." For most of us, we cannot tell the difference between the graphs Jay gives us or the data points given by manufacturers with Pulse machine data.
As a suppressor user and dealer, and hearing real live customer reports, what I have observed is this:
1) Trust the "good names" in suppressors. actually, those correlate well to Jay's findings, as a brand.
2) Suppressor materials, geometries, sound reductions, and production methods have grown more in the last 3 years than the last 30 (subjective, but something like that I believe)
3) 10 years ago, suppressors were sold based on who had the best marketing budget, and the buyer really did not understand what went on in the tube. That has changed, and many brands that had great marketing have been shown to have very average products.
4) The .300 BLK is the easiest round to suppress if you are shooting subsonic. 220 grains is my favorite load, and even a poorly designed suppressor is going to do well.
As an engineer, you might be trying too hard. Read Pew Science, get an idea of which brands consistently perform better than others, and then pic 3 suppressors. Only 3. Trader Joe's philosophy is that more than 3 leads to analysis paralysis. Maybe present your use case here and get 33 suggestions, which will aid in your analysis paralysis.
I could give you my three, but they will be different than your three.
Most .300 BLK buyers want a short gun used for in-home or in-the-truck self-defense. Some want under-the rail performance, which leads to a rail selection that is large enough.
Good luck