it's more of a server issue than player connection issue unfortunately. jp players living in japan playing on jp datacenters still have varying speeds of mudra activation, and the same with players near the montreal datacenters as well

the laggier you are on average (i've personally found that ramuh ex/fcob are the laggiest) the less value skillspeed has because you clip into your gcd more and more. hopefully they fix the delay, or at least make it standard across all zones/instances