They take what they fund. Also, when patents are involved, the big company that ends up acquiring it often uses it to discourage innovation outside their company. So, quite different from a patron model in practice due to incentives.

Now, this doesn't stop a company or VC from acting like a patron. We've seen a number of them release open-source software, publish papers on working strategy/tech, sponsor R&D that is similarly public, and so on. I'm not sure what the percentage is but it shows the models aren't exclusive. It's just the incentives shift VC stuff far in another direction from Da Vinci or Michelangos making goods for the public. Really far per some billionaires. ;)