How much time? In Stormblood, MCH was released in a seriously underpowered state, it got mechanical changes and buffs at 4.05 and 4.06 that happened within 2 months, but then it remained in the shadow of BRD for 16 months until it was buffed at 4.5 to finally be on par with other jobs. Not really looking forward to playing a dead job for the whole expansion again. Not to mention, our ping issues haven't been fixed for like 2 years now. Since it took them over 4 years from NIN release to realize they might have a problem with latency, I'm not really holding my breath for MCH changes, but I really don't want to wait another 2 years until 6.0 to have those fixed.
So far they haven't even mentioned making changes to ranged classes so we definitely need to put the issues on their radar.