The UK has two clearly top universities (Oxford and Cambridge) for a population of about 60 million. I don’t think the US top 10 can fully match that quality. The typical strong US university is no better or worse than a typical strong British university. In terms of rankings of research output (for example based on citations), Britain does at least as well as the US (with less spending).
The US is unmatched as a combination of population size and modern industrial power, but it is not intellectually dominant in the world.
I think the main reason that the US (and even more so Australia) are attractive for foreign undergraduate students is that there is a relatively feasible path to permanent residence (compared to current UK policy anyway).