Let's add a little reality to this perspective:
90 Neck Only available from SECOND Coil. With i90 or higher requirements.
90 Ear-- Only available by defeating Titan EX or from Coil. Both with i70 or higher requirements.
90 Waist-- Craftable. Very expensive. Prohibitively expensive for someone hitting their first lv 50 class.
90 Wrist-- Only available by defeating Ifrit EX or from Coil. Both with i70 or higher requirements.
90 Ring1-- Easiest to earn costs 385 Mythology, very slow to earn unless already doing Hard mode dungeons. One ideal per class type.
90 Ring2--Ideal 2nd ring only available by defeating Garuda EX or from Coil. Both with i70 or higher requirements.
What does this mean?
Only 3 items of your list of i90's can even be cheated on without having ever stepped foot into a hard mode dungeon.
Lets re-tally your numbers then, based on what accessories ARE accessible, under a best-case scenario.
10 Weapon
10 Head
10 Body 70 Neck -crafted via old philo mats x9
10 Hands 70 Ear -crafted via old philo mats x9
90 Waist 70 Wrist -crafted via old philo mats x9
10 Legs 90 Ring1
10 Feet 90 Ring2
Average ilvl 45
So. Too low for HM,CT, Coil. Too low for even WP or AK.
Sure, if you made ALL the other gear i20, you would barely qualify as i50, but would be unable to function.
At any rate, why someone would spend SO much gil on attaining those accessories (as they couldnt realistically be earned by farming) ...without putting any consideration into their core gear, is beyond my comprehension.
...and this silly way of circumventing game mechanics is so unusual that VERY few would even consider it. By then one should at LEAST have the AF sets, which is considered low-end acceptable in lv 50 dungeons.
If I walk into a HM dungeon and see a tank with sub 3000 hp, I will be asking questions, and if unsatisfied, I will leave.
TL; DR ---Players have standards that make your example of cheating the system irrelevant.