1. protocol vulnerabilities in brc-20 can be patched via open indexers, but without bitcoin's script enforcement, divergences persist until social consensus—ln's updates fix code but retain on-chain backstops.
2. centralization here means indexer dominance (e.g., unisat controlling balances), akin to mempool providers influencing tx ordering or acinq's liquidity hubs, but brc-20 lacks p2p balancing options.
3. congestion from inscriptions does strain bitcoin's mempool and fees, making it an issue for core usage, similar to any scaling experiment testing limits.
4. scams are universal, true—nostr relays or ln nodes can rug, but brc-20's off-chain nature amplifies fake token illusions without easy on-chain recourse.
certik on brc-20 risks
https://www.certik.com/resources/blog/ordinals-and-the-brc-20-standard-overview-and-risk-analysis