Yes, not dissimilar from torrents. Instead of being name-addressed and requiring the name owner to provide the infrastructure to serve the data (as with HTTPS), data are content-addressed so that anyone can serve the data.
Many NFTs are hosted by NFT platforms, and also by services such as https://nft.storage/ (backed by IPFS & Filecoin). It's quite trivial though to take the IPFS CID and pin it somewhere else (local computer, a pinning service like Pinata, etc.), and anyone can do it at any time. If all you want to do is be able to prove ownership at some point in the future, you don't really need to host the content indefinitely on IPFS...just host it when you need to.
Many NFTs are hosted by NFT platforms, and also by services such as https://nft.storage/ (backed by IPFS & Filecoin). It's quite trivial though to take the IPFS CID and pin it somewhere else (local computer, a pinning service like Pinata, etc.), and anyone can do it at any time. If all you want to do is be able to prove ownership at some point in the future, you don't really need to host the content indefinitely on IPFS...just host it when you need to.