(1) "Buying" a Rolex (or knockoff) vs NFTs - buying a physical (or digital) good gives you privileged access to it. The same is not true of an NFT, which just adds your name next to a pointer in a (decentralized) database. Nothing changes in regard to access to the underlying good unless people decide to build mechanisms on top of the chosen blockchain to artificially enforce access privileges, but you don't need a blockchain for that (cf. skins in CS-GO or stock images one pays for to purchase and download).
(2) "Indistinguishable" - with physical goods, that's a perceptual property and when you're talking about knockoffs of luxury goods, it really just means "hard to tell the difference (unless you examine it closely)". With digital media, the way it's been set up with NFTs, indistinguishable means completely identical. There are ways to actually sell protected digital media - e.g. you show a low-res version on a website and only send a full-res version once a purchase is made. But that's also been happening since the internet became a thing and doesn't need blockchains or NFTs either.