I think they decided that the whole saga around Horny Horner was enough "shaking things up"

Now watch Max wrapping up the constructors on his own like he did last year.

Money definitely is a big factor I'd guess. Checo brings in a big part of the team's overall budget. Also he is embedded into the team by now and why try an unknown change when you don't have to?

Paddock rumours also say Horner didn't want to promote one of Marko's juniors on purpose.

To be honest, Perez was always a good driver. Perhaps RBR knows that the car isn't really where it appears to be, and it's Max that brings it there. Then another driver would not make a difference. And with Perez they know they will not have an intra-team war like Merc did with Rosberg and Hamilton.

Audi or Williams, it's rumored.

I’m pretty sure Sainz Sr. races for Audi so it would make sense in my mind

I don't think there were concerns regarding that. The main issues are Perez's seemingly repeat of a slump and Ferrari closing in on points, potentially costing Red Bull the constructor's championship this year.

Frankly who is at this point¿? With Hamilton and Alonso fading with age, I don't see who can match max over a season. Leclerc, Lando and the others haven't honed their consistency to the level that max has. 2020 and especially 2021 have greatly improved Max's consistency upto the point where he is maximising things every race