I'm not saying that Max has a problem with it, I'm saying that Red Bull has seen what happened at Mercedes and do not want that at their team. Max might not have a problem now but two equally matched drivers in the same team tend to lead to complications that might end up costing the team. See Senna vs. Prost or Hamilton vs. Rosberg or even Norris vs. Piastri this year. (or even Gasly vs. Ocon at Alpine)Come on, thats bull. Max never had any issue with Red Bull trying to get Lando into the RBR multiple times and if there's anyone that could get close to him on speed it would be Lando, Max doesnt feel threathened by any driver and if a driver beats him he makes no issue of it, he's never made any negative comment about Checo when he won GP's and beat Max except to say he himself should do better.
Red Bull passed on Carlos Sainz specifically for that reason (and also because Carlos Sainz sr. and Jos Verstappen hate each other's guts) and the most effective Mercedes pairing was the pairing of Lewis and Valterii where the hierarchy was clearly established.
Red Bull do not want someone who can challenge Max, they want someone who is an effective second driver. That's why they went for Ricciardo or Lawson over e.g. Sainz.
I'm not even sure that Red Bull would try to hire Lando again after this year because of how much he improved as a driver