OpenSea has raised over $470 million in VC capital [1].
That means that they will easily crush their competition and cement themselves as the home of NFTs. And then of course their "filtered view" of NFTs will become the source of truth and not the blockchain itself. And they have shown they are happy to do this filtering when asked [2].
[1] https://www.crunchbase.com/organization/opensea/company_fina...
[2] https://cointelegraph.com/news/opensea-freezes-2-2m-of-stole...
Centralization is worse in NFT land. The NFT industry is Axie Infinity, OpenSea, and the little guys. Back end mostly goes through Metamask. Few people interact with the blockchain directly.
Metamask can and does blacklist coins and wallets. OpenSea can and does blacklist NFTs. While in theory you can go around them, they can seriously reduce the value of assets at whim.
To get an NFT onto Decentraland, there's a US$500 "curation fee".