Long before ETH was even a glimmer in Vitalik's eye there were NFTs on bitcoin. They were called "colored coins".
Then when another second layer known as CounterParty protocol was designed, that enabled NFTs,... such as Rare Pepe:
The reason you don't hear much about this is ... well bitcoin (purposely) does not have a robust enough smart contract architecture to make NFTs easy. Bitcoin is for censorship-resistant payments, not for storing hashes for jpegs. But there are other second-layer protocols that have better support for NFTs.
NFTs around Bitcoin:
  • Counterparty
  • Liquid Network (see Raretoshi.com, Infinite Fleet (game, with NFTs))
  • RGB
  • RSK
  • Other emerging protocols that enable tokens on Bitcoin
Tokenised Securities & NFTs on Bitcoin with Adam Back & Samson Mow — What Bitcoin Did #1941 https://www.whatbitcoindid.com/podcast/tokenised-securities-nfts-on-bitcoin-with-adam-back-samson-mow