Support for the artist exists when someone first buys the NFT from the one who minted it. But nothing prevents investors from trading NFTs among each other. How many NFT trades are "artist-to-buyer", how many nft trades are "investor-to-investor"?

And if I buy a piece of art the classic way (buyers contract), I can put it in a gallery, or whatever, and "show everyone that I support the artist" that way.

And even without buying something, no Blockchain is required to support artists: people have managed to do so since long before electricity was discovered: https://en.wikipedia.org/wiki/Patronage#Arts