IPFS and distributed filesystems have nothing to do with blockchains.
In fact, while F2FS is a ludicrous example, this happens regularly with filesystems. The core design of filesystems is still built assuming that a block device will be behind it. IPFS is the same way, just s/block device/blockchain/.
- You can have files on IPFS and no blockchain whatsoever "behind it".
- IPFS itself makes no use of blockchains as an abstration for data storage or file organization
- If all the blockchains networks and nodes disappeared overnight, no IPFS nodes would be affected.
I don't know if you actually used any of that or just going by hearsay.