Tell him nothing. It’s not his business.
Does he do it to Thai customers, no, he just drops off and leaves. You deserve the same respect.
Thailand is a class society. Taxi guys, maids, delivery guys, are lower on the scale then customers. Overly friendly chit chat on the job is a way of bringing you down to their level and you lose respect if you do it.
if he baits you and you get annoyed you’re drawn down as well. Just a thank you and door gets shut.