Does thrill of the hunt cancel blitzcrank trigger

Yes — Thrill of the Hunt can make Blitzcrank's pull whiff, though it doesn't literally cancel the trigger: the ability still goes on the chain, then resolves and does nothing.

Blitzcrank's "when you play me to a battlefield" ability goes on the chain with its chosen unit (FAQ #2899, #1183 — you get a response window before anything is dragged). You respond with Thrill of the Hunt on your own unit, banishing it to a non-board zone and replaying it as a brand-new object, which severs the targeting relationship so the pull ability mistargets and fizzles (Rule 359.3.e; FAQ #12278). It only works because you can react, and only for the unit you banish — one Thrill covers Blitz's single target.

Two caveats: your unit comes back as a fresh object, so anything attached or granted to it (gears, buffs, "this turn" effects) is gone, and you choose which battlefield it's replayed to. And Thrill only banishes a friendly unit, so it can't touch an enemy Blitzcrank — his "when I hold, return me to my owner's hand" trigger is unaffected.