H1Bs may or may not be good. Local workers may or may not be good.
The larger issue is the use of H1Bs by the various subcontracting pimps.
If Google or Msoft is directly sponsoring an H1B, they're doing their due diligence on who they're getting. It's arguable whether that is "good for the country" or not. It probably is.
But the majority of H1Bs are going to subcontracting pimps, and they aren't scouring the world for geniuses. The warm body orgs aren't hiring the best and brightest, they're pushing who they have in their systems, and under their thumbs. Who they have the paperwork on.
The decision that the true hiring org makes is which pimp to procure from, not which genius to hire. It's hugely corrupting to the businesses involved, as the slush fund generated by taking 25% off the top of dozens of salaries is huge, so that millions of dollars turn on which pimp gets hired. If you think that none of that slush manages to find it's way back into the pocket of the corporate decision makers who choose the pimp, you are deluded.
Corporations corrupted, shareholders robbed by middle management decision makers, citizens put out of work, labor laws evaded, disposable human cogs imported to the country, who often plan on leaving, and thereby are willing to take legal risks in a foreign land, knowing that they'll be getting out of dodge in a few years anyway.
What's not to like?