But it is definitely possible to implement NFT directly on Bitcoin; simply through using a
coloured coin.
To be honest, we have these for years and they can directly act as an NFT without any modification to the spec.
Colored coins prove majority of Bitcoin community don't really care about NFT/token which shown by lack of interest.
What we need to keep in mind in topic of NFTs (or by extension tokens) is that there has never been any connection between the token and the underlying object whatsoever. For example in case of artwork (digital or physical) it is an arbitrary data (eg. a hash) that is stored in a blockchain and a non-existent link between that data and the art.
For some people, it's not connection between NFT/token with object. NFT is proof that you're legitimate owner of the object, although it has no legal power and many people don't care about it.