People are forgeting that especially before the cost cap we had teams literally spending themselves out of bag well ahead of others.
Is the only solution then to also give other teams more money to spend? Say when United or Arse were dominating the PL, Barca or Real La Liga or Bayern the Bundesliga - should they all had their resources clipped or other teams have been given more of the league and broadcasting cuts to close the gap? In theory this cost cap and wind tunnel time increase is arguably a very solid concept to prevent run aways but at the same time does that mean its unfair to teams doing the work better than others? It's honestly a bit of an odd phenomenon - F1 is far less of a elite vs non elite team sport now than it was for decades.
I'd argue the biggest reason why we don't see gaps being closed is mostly down to regs being far more restrictive than during the previous Merc and Ferrari domination eras. Teams are a lot less able to introduce crazy concepts to gain an advantage. And even if they do- say the double diffuser, the old regs allowed the more powerful teams to rather quickly apply it to their own cars and improve upon it.
Edit: p.s. I do agree I wish RB had a more competitive driver in the second seat.