You might well be listening to your system in the range of 80 dB SPL to 85 dB SPL, thinking that you're hearing 100-dB levels. Subjectively, a playback level of 85 dB SPL is describe by most people as "quite loud". Levels 10 dB louder, 95 dB SPL, are termed by most people "very loud," and, with the exception of amplified rock music, typify the peak levels experienced from most good seats in a concert or recital hall from orchestral music. (Amplified rock music is something else again.)
I think the general reluctance to believe that an AV receiver's internal amplifiers can handle most of the demands of very loud music in typical rooms is partly due to the tendency of lots of listeners, after getting "sauced up", to crank up the playback volume to extremely high levels, thus testing or exceeding the limits of a receiver's internal amplifier, or pushing it into distortion. It's why I still endorse having "as much power as you can afford", as a kind of audio "insurance" for those times when you recklessly crank up the levels. With several hundred watts of power in a separate power amplifier, you can be assured that you're unlikely to drive the amplifier into clipping (and possibly damage your speakers from distorted clipped signals) even when you're "sauced up" or stoned.
I don't advocate long-term listening at such levels because of potential hearing damage, and I've been known to flee Axiom parties when levels became ludicrously loud, but I don't deny the thrilling sense of power that comes from owning separate power amplifiers for those moments when you want very clean undistorted output for 100-dB-plus peaks.
By the way, thanks for your compliments on my article.