Ok, if you say so. I just trust the guy doing my smogs. He has no skin in the game unless they could pull his ticket for passing modified vehicles. And they do perform stings on smog shops here.
You can't fail smog or anything with a VFTuner Tune. Dealerships don't even notice it.
It has never denied a warranty claim.
Sounds like your smog guy is basing things off his experience then generalizing all vehicles.
Yes, there's a lot of tunes and modifications that will fail a smog test due to increase of bad exhaust.
But all of the tunes available to Tacomas without F/I is smog safe.
He's not adapting and learning with advancements in tunes. VFTuner flashes can't be detected.
It's understanding what the tune actually does. These tunes change shift points and may try for more power during driving.
Smog tests are at idle... think about it.
The only way is for you to openly disclose it's flashed. Even then, the test won't notice a difference.
It would just be a cautious or by the book inspector thought would fail the vehicle.
If anything a VFTuner tuned vehicles would have better smog results.
Smog tests are done at idle for excess and harmful pollutants.
Tunes will smooth idle out. Smog will read higher when factory idle is jumping around.