I think of a "tech" trick as a difficult spin with a difficult grab (unnaty, switch, double grabs, screamin seaman, genie...ect.)
I would defiantly say that a zero spin is for sure a "tech" trick, I might get some disagreement on that, but we all know how announcers always have to explain how Difficult a zero spin is.
Tech ≠ a sloppy 10 that some kid barely hucked off a tiny jump