I think Red Bulls priorities have changed since the death of Mateschitz. He was more interested in sporting success itself, the current owners are more interested in finances. And for marketing purposes the WCC doesn't actually matter much, it's only the Driver's Champion that people really care about, hence also what sponsors care about. Mercedes won the WCC in '21 but nobody cares or remembers. And the marketing upside Perez brings (at least so far) has been very enticing. I don't really get why (might just be fiery nationalist pride) but Perez is unspeakably popular in Mexico - and even extended to Latin America in general. As far as I know he sells the most merch in the entire sport and brings in the most sponsors. He brings a huge amount of value for shareholders.

i think it's about the market in south america. saw multiple comments on reddit explaining it like this: RB doesn't care a lot about the WCC, they would obv like it, but the WDC is their main target. also makes sense, as this is the thing that is publicly most known and advertised with. RB still won the WDC and has a big market to successfully advertise in with perez in south america. they actually got what they wanted. and i kinda believe it to be the reason. i mean, they are not dumb, they know, perspective and WCC-wise, that Perez is not the option.

You are correct. But the question the shareholders will have to answer is whether he can be replaced by a better driver. The only driver doing well next to Verstappen was Ricciardo.