If the local market for American DBAs is $180k, then hiring H1B DBAs at $110k does depress wages.

Sure, but if the local market is that high you probably have sever supply constraints.

If you don't fix the supply constraints, you'll depress growth.

You could fix the education system - good luck - and then wait 5 years before you cut H1B.

But yes, obviously it depressed wages, which at a certain point is probably a good thing.