I've not followed this thread.. but in the german forum it was said,
that everyones gil (the gil of the whole economy in a total)
is being reduced about 1/10 (90%) of the original gil.
the new gil cap is just a result of this because 99.999.999 milion gil are 10% of 999.999.999

so you wont lose your gil because everyone's gil is being reduced. you will stay as rich as you are now in the same value compared to all other players. the only difference is, that we have much lower inflation and gil is much more worth as now.
and that the difference between old and new players isnt that big anymore. i really thing that this change is aussum. we do not need 999.999.999 gil for a player..
an other good thing.. gil seller wont like this

bot characters/gil farmer chars carry hundreds of million gil with them and so they just can have "only" 99 million per character. it will hopefully mean less inflation then. (gil will be much more worth then)