Yeah that's fair of IPFS. 

Blockchains I think would not function on an interplanetary scale  so long as they are based on the relativistic time of one of the planets. 

If blockchain currency becomes standard and doesn't account for this then we'll see planets aquiring or shaving mass to affect their relativistic time in the same way we see nations manipulate their fiat currency now. 

Interplanetary blockchain would have to be based on entropy with a high degree of accuracy, I think.