Another point is that chip suppliers can pick their customers until supply issues resolve, which there's no sign of.
Should chip suppliers view open-source drivers as undermining their competitive advantage? I don't think so, but they tend to, and this isn't a great time for RasPi to get on their bad side.
It's also not their mission, although that's been pointed out enough. Call it a battle for another day.
> they could be using these very same chips, but with an open source driver.
You are not understanding the issues. If it was an option, the Rpi foundation would have taken it. Shipping closed drivers, to an opensource project is a ball ache, and leads to lovely people claiming that the foundation is there to stifle this and under mine that.
Its far more dull than that.
Its either a compliance thing (opensource drivers might need re-certifying the wifi) Contractual: its a seller's market and in order to get the best value, the foundation had to use the drivers provided.
There is a chip shortage on, so having a volume supply wifi chips is a miracle.
Not having to pay a licensing cost is also rather a good deal.
As with all things here, perfect is the enemy of good.