An 'RMS Compressor'

[Trebor]

... idk if technically 'Limiter' is doing a compression but it's more of a hard cut ...

Audacity's native limiter has hard & soft settings.

[kozikowski]

We have super different goals.

ACX is pretty clear that they want human speech as natural as possible with no distractions and within certain loudness, peak and noise boundaries. The Audiobook Mastering Suite and ACX Check...

https://wiki.audacityteam.org/wiki/Audiobook_Mastering

...were designed to provide performers the tools to produce those works and test them before sending them off to be evaluated, accepted and published. As near as we can tell, this protocol works spectacularly well and we have a terrific track record for getting people published.

If you don't start with a Mono spoken performance from a human voice in a quiet room, then your mileage may vary. A lot.

You are doing the compression product evaluation for loud, dense stereo music. Write down how it goes. You may get a music processing package named after you.

Koz

[aud2019user]

"limiter has hard & soft settings"
that 'soft' is what I mean with 'technically doing a compression' but ends out being hard nonetheless...

If not just "RMS Compressor", it should be named after the person/s that actually do the coding to make it happen;
another name proposal: "The Great Music Equalizer"

[aud2019user]

With standard 'Compressor' some common cases to get to aprox. RMS -9.3 OR -9.5db [Peaks 0db]:
[for all this examples: 'Noise Floor' -40db, attack time 0.20, release time 1.0, ticked both 'make-up for 0db...' and 'compress based on peaks']

*from RMS -10.5 > apply Compressor Threshold -15db, Ratio 10:1 [or Threshold -10db, Ratio 10:1]...
*from RMS -13 > Threshold -40db, Ratio 10:1 [or Threshold -20db, Ratio 10:1]...

*it could need just a Threshold -2db, Ratio 2:1...
*or require 2 passes [eg if the selection is mainly Peaks way lower than 0db ]: a Threshold -40db, Ratio 10:1 and then a Threshold -4db, Ratio 4:1
...