And when McDonald beat Tiafoe earlier this week top college players were thee ones again ?

Very rarely a good idea to fix on individual results to try to make out a much bigger case, especially to talk about some "gulf". Players are just overall not consistent enough that one can make judgements, especially such a strong judgement, from one or two matches. 

Kind of reminder of Edmund beating Evo outdoors in Texas in February ( even if pretty decisively ) so therefore supposedly no debate that Edmund was the guy for the Davis Cup indoors in Glasgow in September when there was so much else to consider. Overall his final selection seemed fair enough, but never just on that one match.

College tennis being very much my non specialist subject I can't really comment much further and Oakland may or may not have a decent case, but it does not come from these matches. I am guessing that it is open to debate with many factors to consider and almost certainly one size not fitting all.