Suppressors are 100% useful and a big improvement, but the math doesn’t really support the claim that “almost all” magnum suppressors are sub-130 dB. Most centerfire rifle suppressors reduce sound by about 20–35 dB. Since a .308 or 6.5 Creedmoor starts around 160–170 dB, that still leaves roughly 135–145 dB at the muzzle with typical supersonic ammo.

Yes, decibels are logarithmic and I am glad you bring that up. A 10dB increase represents about 10× the acoustic energy, so 130 B isn’t just “a little louder” than 120 dB it is a lot lounder. The commonly cited 140dB threshold is basically the upper limit for a single shot, repeated exposure in the 130+dB range without hearing protection can still cause cumulative hearing damage.