It's not misguided and arrogant at all. It's based on reality. An absolutely enormous percentage of the world's population would go to the U.S. if they could, because they know it's a place uniquely easy to start a new life and succeed. Even if you're there illegally. There is no other country like it in human history in this respect.
It's totally absurd that it's "discriminatory against Thais." The great majority of Thais who apply receive visas -- how is that RACIST? AND -- many Thais have shown what they'll do if given the chance -- something like 400K Thais in the U.S., only a small percentage of whom emigrated legally. MOST of the Thais I know who have some sort of ties to the U.S., when you really talk about who went there and how, somebody overstayed a visa or did it through a sham marriage.
If anything, the Embassy isn't being tough enough, looking at the facts. Again, feel free to suggest a better system. Again, feel free to describe how the Embassy is RACIST!!!!! Or you can just keep repeating that (I can guess what you'll do).