Park admission increases enough without trying to tie it to or justify it with changes to Fantasmic. How about they use some of the recent increases to finance any needed upgrades?That's what we're talking about - increasing park admission by way of making changes.
Fantasmic! will survive as long as it continues to contribute in terms of park admission what it has always contributed. When we guests decide, through our assessment of value, that Fantasmic! isn't worth it anymore, then it'll end. If we guests decide, through our assessment of value, that a certain change to Fantasmic! will make it worth more to us, then it'll be changed. This isn't rocket science.
To insinuate that a ticket increase is required to cover any upgrade is to insinuate that there is no reasonable profit being made at all.