Mane the best winger in the world of football played for RB. Haaland, on his path to becoming world class, aswell. Daka is scoring at a rate almost similar to that of Haaland and linked to several top clubs. We already had a 15m bid on Adeyemi rejected when he was 17 and played for RB B (!). That should tell everything about his talent. I don't see how this is a "bunch of low key, fancy names". But buying players from lesser teams for a good price who are showing quality are the way to go.
This is what Liverpool and Bayern are doing. Alphonso Davies performs as the best LB in the world and Bayern got him for 12m from Canada. Or what about Robertson, Van Dijk, Gnabry, Keita, Matip, Kimmich etc etc. All of these were brought from lesser teams and neither teams are on the way to mediocrity.
On the other hand, us who frequently overpay for "proven" players from top teams are on way to mediocrity. I don't really see the connection.
I dont say there are no exceptions, like the Haalands and Manes of this world, but identifying them out of a 100 other "lowkey, fancy" names is incredibly difficult. If it was that easy Liverpool wouldnt have been irrelevant in the league for 20+ years. They did fantastic work recently, but its always a combination of luck and circumstances. Fair play to them, but we cant just reproduce that. Keep in mind that we had MUCH more success the last 5, 10 or 20 years.