Falcon-512 sigs are ~666 bytes vs ECDSA's ~72 — nearly 10x the per-tx footprint. DOGE can absorb that better than BTC with its 1MB blocks and 1-min block times, which is probably why they ran the experiment here first among UTXO chains. But OP_RETURN proofs don't protect UTXOs at the consensus layer — until nodes validate Falcon sigs natively, this is a demo, not a defense. Algorand already ships Falcon in production; for UTXO chains, the bottleneck isn't the math, it's the hard fork.

Top comment by @Benthic