You can measure and model a cartridges performance...
I have an excel spreadsheet - which is a bit complicated to "drive" - but fundamentally it models the electrical behaviour of the cartridge (taking into account capacitance, inductance, and impedance.)
You first measure the frequency response of the cartridge/stylus/loading in real life...
Then you "deduct" the modelled response from the measured response...
The result will be the sum of all the non linearities - the biggest one is cantilever resonance(s)... but you can also have eddy current losses and other effects...
You then rerun the model, using the non linearities measure to adjust a choice of parameters (inductance, impedance, capacitance) - you can even use the spreadsheets target seeking modes, to try to find an optimal setting.
It is NOT perfect... The model clearly requires more work, and some of the non-linearities should in fact be built into the model....
BUT - it does consistently predict "the gist" of the end result.
So I can take a cartridge, measure it, use the measurement to estimate an optimal loading - adjust the loading and measure again to see where I am at!
One of the things that this sort of exercise shows up, is that with many cartridges, we walk a fine line - we can opt for a more extended frequency response - achieving perhaps +/-3db out to 20kHz - or we can opt for a much tighter F/R over a more limited range of frequencies - with a rapid rolloff thereafter - so for many cartridges you can achieve +/- 0.5 db out to 14kHz - but then a very steep rolloff after that, whereas the alternative (achieving +/-3db to 20kHz) has rises and drops.... so the cartridge definitely does not sound neutral.
You can also easily (relatively easily...
) visualise the proposed "Voicing" and see what the rises/falls in F/R will be with a specific proposed loading.
Fundamentally - in a theoretically perfect world - I see no logical reason why one wouldn't use this kind of measurement to develop the same kind of EQ we use for Speakers and Rooms to achieve desired target curves with cartridges.
Choose whether you want a neutral (flat) frequency response, or one with more presence, detail, bass.... etc...
Then one can choose the best tracking cartridge possible for your individual setup - and use the EQ to tune in your optimal "Voicing" - rather than buying megabuck cartridges to "voice" things the way you like them...
The old Carver trick of voicing an amp to sound like a different amp - is even more applicable to cartridges.... in a blind test, I doubt most people could tell two cartridges apart if they had been properly set up like this, with matched voicing.