Whether you believe bitcoin should have more L2's or not, the paper starts out with a great market analysis on bitcoin L2s using that-other-chain's L2s as a basis. It hadn't occurred to me that that-other-chain's L2 ecosystem solely exists to scale its L1's space/compute/economics and that those L2s end up competing directly with the L1. Most of the talk about L2s on bitcoin also include talk of more functionality and there's always the assumption that there's a major security tradeoff taking place, so it seems unlikely a bitcoin L2 would compete directly with the L1.