Discounting Combat and Acrobatics... You have a hero with some knowledge specialty, like Tech or Science. They use some mechanical or electronic gear that's essential to their character. Do they add the specialty in for attacks? Reactions vs attacks targeting the gear?
For example, Spider-Man's mechanical web-shooters. Would he add Tech Expert to web-related rolls? Just when attacking with webs? If a villain tries to destroy the shooters? Or even when a web-related complication is being targeted? And then if he gets organic web shooters, does the specialty no longer apply?
Other examples are Doctor Octopus and his arms, Green Goblin and his glider & bag of tricks, or Mysterio and his mechanical illusions. Or the Punisher and his arsenal, even.
I would see Tech being used to build those things or repair them. Or to be used when attacking something technological (from identifying its weak points, for example). Using it on physical action rolls with your normal gear feels a bit weird to me - it seems to me that there's a difference in being a skilled combatant (pulling a trigger, pressing a button, throwing a bomb, etc.) and a skilled inventor.