Look, this isn't about the visa holders themselves. This is about the spouses they bring with them being able to work legally. Btw, no other country I'm aware of allows this. If you're brought in on a high skill visa, generally spouses who tag along are not allowed to work.
And in no way are H1B visa holders "Americans in waiting". Their visas are supposed to expire the moment an American can be hired with the skills to do the job.