On-chain settlement speed for large commercial volumes

Been diving deep into stablecoin rails for commercial payments, especially for bridging the gap between traditional finance and crypto-native businesses. Everyone talks about the instant settlement aspect, which is great for micro-transactions or small-to-medium transfers. But when you look at really large-scale commercial volumes, like processing multi-million dollar transfers, the finality on most chains still feels like it introduces a non-trivial time lag compared to a simple internal ledger transfer within a bank or payment processor. We're talking minutes versus sub-second. I get that the decentralization and censorship resistance are the trade-offs, but for a business that needs to move significant capital quickly and confirm it on their books, is the current on-chain settlement speed truly ready to replace legacy systems for all high-volume scenarios? It feels like we're still in the early innings here, despite the narrative. Would love to hear if others are seeing this play out differently, especially those dealing with larger throughput.