That's the problem with the use of the PRMG in my view. If you want perceptual (i.e. compression only) rather than saturation intent (compression & expansion), you are out of luck.
You get a much better define and accurate transformation using a device link or device profile with a source space specific perceptual (or whatever) gamut mapping, rather than relying on the PRMG fudge.
That's the odd thing. The ICC sRGB reference perceptual profile doesn't compress, it mostly expands the gamut.
For instance in a colorchecker image the two colors most affected are cyan and yellow. If I set Photoshop to perceptual, attach the ICC v4 sRGB profile to a colorchecker card image that is in standard sRGB (only cyan is clipped in sRGB) then print it on Baryta SG canon 9500 II using perceptual both the cyan and yellow are printed with far more saturation than is possible in a standard sRGB gamut.
For instance the cyan patch comes out at Lab=(36, -29, -44) and the yellow patch prints at Lab=(83,13, 97). Both of these are over 10 dE from the sRGB gamut boundary.
Basically, if you want color "Pop" from an sRGB image that profile is one way to get it. It happens because the PRMG is larger than sRGB so they re-map (expand) the sRGB gamut to the larger PRMG.
It's sort of like making a silk purse out of a sow's ear.