Cosmos Hub validators already have their hands full with governance responsibilities. ICS (interchain-security) is the next challenge they will face, as each new chain will use the Hub's validator set. Data-availability will be an additional burden for validators to grapple with.   https://i.imgur.com/Y9iBUDD.png

orthonym | working for the interchain foundation | lives mostly in cosmos | 
psuedonyms: 
abra tusz |
ala.tusz.am

as for concerns about reliance on "super-full-nodes", Celestia will support partial-storage nodes: https://github.com/celestiaorg/celestia-node/issues/1133

for those interested in learning more about celestia, and this problem in particular: https://www.youtube.com/watch?v=NrRQkrA-b4c

this was referred to me on twitter via this thread: https://twitter.com/FeelTheDefi/status/1616024263764361217