I generally agree with your sentiment here but there is a difference between an IOU and an IOU that can be redeemed on chain unilaterally.
Discussion
What is the meaning of 'unilaterally'?
If it means trustless trust, like LN-BTC, It is not an IOU. Unlike this, if some permissions are required, It is an just IOU what I'm talking about.
Liquid requires trust to redeem.
nostr:note1hqcvj22tlxn63zq4n3aq82tvv59g99gff9t0m579hkufznn4c98qfl8hga
Agreed, although in practice there's decent liquidity that doesn't require an official peg-out with liquid. Perhaps bitVM can give us a real trustees two way peg? Although it sounds over hyped as of now.