Are there usable NFT gaming tokens on bitcoin's network already? Is there an NFT marketplace? You didn't seem to link the article so these aren't things I'm able to quickly find, but I doubt both at the moment (the main nft gaming platforms are still in altcoins).
The answers are yes and yes. The first Bitcoin blockchain game was called
Spells of Genesis, launched in 2015. It used Counterparty tokens for gameplay and players could also earn tokens through completing certain aspects of the game. Some of them are now worth
serious bucks as collector's items. Bitcoins 10-minute blocktimes are an inherent drawback to using it for gaming but peeps have found ways around it through the years.
An Ordinals market has yet to be developed, although the other day the ordinals "team" put the finishing touches on a wallet that makes it easy to transfer them. Counterparty has enabled token trading through its DEX since 2014, and in 2021, it became possible to vault contents of BTC addresses and wrap them as ERC721 tokens for sale on OpenSea (this is by far the more popular route).
I also doubt adding to an ecosystem can detract from it. There's no suggestion bitcoin can't be used as money and have NFTs on its blockchain.
Word, an entirely sensible proposition.