I mean Hextech has no other effect and giving up an entire synergy can be an issues, especially if the Champs you're using are also lacking in power compared to others.
The only issue I see is the fact they're support GunslingerXBlademaster which is quite busted already!
When fights end with Hextech debuff being only halfway through... SURE that's an issue!
But that's not really the fault of Hextech tbh...
Maybe that or it's simply because I focus on strong Champions with strong synergies that don't rely on Items that much.
You find me around Imperial/Knight/Sorc/Brawlers almost every game and with the names of Blitz/Cho/Seju/Swain/Draven/Karthus on board having Items is neat. But not really required.
The only thing the REALLY bothers me is Hextechs interaction with Spatulas... I'm not sure, but I think it kills the synergy and I'm not convinced it returns as it should once effect runns out! As a Yuumi addicted THAT's an issue!