Bitcoin developer René Pickhardt says self-custody security concerns kept him from accumulating more BTC earlier.Coldcard vulnerabilities made some wallet seed phrases predictable, exposing users to remote key recovery attacks.Galaxy Research estimates roughly 1,755 BTC was stolen across several waves linked to vulnerable wallets.Coinkite says patched firmware cannot repair previously generated weak seeds, requiring users to migrate funds.Adam Back argues Bitcoin self-custody remains powerful but requires users to accept greater security responsibility.