Some of his points are out of date (given state of the art is old), like royalties and immutable data. See ipfs, eip-2981, etc.
Other parts are very on point, specifically everyone using opensea as authoritative for NFTs, which is crazy town. Opensea has a dog in the fight, and they are very opinionated about what's allowed in the tent and not. Things like etherscan and infura are less scary. I can't imagine building a wallet and depending on opensea for anything though, because your users are not going to appreciate that choice.