It probably is easier to find someone like Max Aarons. Although not british, and I do think Aarons seems very, very talented. He is great attacking and a very good defender (better than TAA, I would say).
AWBs ability as a defender probably makes him more unique/rare and more exceptional. We do not see defender that solid very often at this level. Without the ball, he is van Dijkesque. But I do not agree that it translate to him being better overall or of higher value to a top team.
AWB overall, in my opinion, looks a bit like fullback version of Chris Smalling on a good day. If that turns out to be correct, and Max Aarons fulfill his potential, signing AWB over Aarons this summer will be a mistake. And because of the fee, I do think it will be a big mistake.
Being an exceptional defender, rather than just a very good defender, is of so little marginal value that I feel certain that AWB will not be among the three best right backs in England in a few years unless you play a very reactive and defensive football. Trent Alexander-Arnold, Reece James and Max Aarons will be considered better overall in a few years time.
This season showed us just how important creative, good attacking fullbacks are starting to become. Its been a trend for a long time. In the years to come, for top teams, it will be even more crucial. You need as many players that can create as possible.
To me, right now, it feels a bit like when we failed to sign Sadio Mane and went for Mhikitarian or some of the other crucial mistakes we have made the past decade in the transfermarket.