James O’Beirne describes the realities of block size constraints, presenting original research and performance measurements. He challenges common objections to larger blocks, arguing that current technological capabilities could support significantly greater throughput without compromising decentralization. O’Beirne emphasizes the importance of enabling self-custody at scale to prevent custodial capture and ensure Bitcoin fulfills its promise as permissionless money.
This presentation was recorded live at 2025’s OPNEXT, the Bitcoin scaling conference. For more info, visit opnext.dev. OPNEXT livestream and VODs are made possible by Taproot Wizards.
To watch the full library of OPNEXT 2025 content, be sure to check out our YouTube channel!
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# Notes:
– Current Bitcoin capacity: ~20M transactions/month
– 300M exchange users could take over 1 year to exit
– Node CPU utilization: only 0.12% on block connection
– 100x current block size = 88% node idle time
– On-chain storage costs: $100k/GB vs AWS ~$0.023/GB
– Bitcoin vs custodial capture existential concern
