The 500 $ Cartridge is on a 10k $ Turntable / arm combination will sound better than the expensive cartridge on a wobbly basis.
what will sound even better is a balanced system 50% turntable /tonearm, 25% cartridge and 25% phono preamplifier.
When it comes to numbers it’s nothing, because your $10k tonearm is 30-50-70% cheaper on the secondhand market, but it’s the same tonearm.
BUT your $500 cartridge can be more expensive in time if it’s a great cartridge like some of those vintage MM or MC, they are getting more expensive if the condition is still NOS after 30 years (and, of course if many users are still fascinated about the sound). Your calculations are wrong, because a $500 cartridge from the 80s today will cost $1500 (for example). You can use a great cartridge on any great tonearm if you like the sound. I’ve heard $450 cartridges on $5000 tonearms and it was a stunning combination in direct comparison to more expensive cartridges.
The system balance you measure in % is nonsense if you will take a whole picture. The balance is only about the sound and you can’t measure it in $ or in %.
Some people are living in the world of High-End Audio press where everything is high priced, they might think they need a system like M.Fremer has. In reality the brain can be totally satisfied with a well balanced and much cheaper system and it's not necessary to follow the reviews for cartridges that cost $15k each.
