Some will drop by more, some iwll drop by less. It depends largely on how supply and demand plays out upon release. If people try to exploit the redenomination, they will quickly find that few people will buy into it. It's just like when money inflates, some prices change more/less/faster/slower than others. People will have to re-psychologically ingrain their pricing, because nobody is going to pay drastically more than they do now just because the currency was redenominated Most buyers aren't any more or less stupid than sellers.
The likelyhood your purchasing power will diminish is negligible at best. it doesn't usually happen in real life, nor will it in the game. Purchasing power decreases when costs go up but income does not. The influx of gil into the system relative to the amount coming out is going to stay roughly the same (Not exactly the same, considering part of the reasoning for the redenomination). Therefore you're not going to see any wild shifts in prices, unless a shift and supply and demand causes it.The likelihood that our purchasing power will diminish is almost a certainty to me.
Finally, any shift in purchasing power will affect everyone by the same porportion. A redenomination, being a simple conversion of X number of units to 1 unit, cannot disrupt this.
This is a non-issue. Everything is scaled in equal porportion. the same portion of gil is applied to all. You need to look as a percentage, not as per unit. There is still the same percentage gap in 1000 vs 100 as there is in 10 vs 1. Both parties lost the same portion of the effort the put in. Both parties have the same buying power they had before.Not to mention the investment in savings can be represented in time, industriousness, and ingenuity. Those who saved will be losing relatively more than those who did not save.
Player A loses 900 points of their effort, while player B only loses 9 points of their effort.
In closing, yes, it is actually a simple math problem. You can try to spin it to look like people with more money are being hurt more, but that is not the case.
The only real impact to the economy being caused here is the removal of a common consumable.