Fyi, it was predicted very early on. The first reply to Satoshi’s announcement email to the cypherpunks mailing list criticized the idea as unscalable. Satoshi implemented an early version of payment channels in Bitcoin Core around version 0.1. https://en.bitcoin.it/wiki/Payment_channels

Finally, some $49B was transacted yesterday on Bitcoin. Whether billions is virtually zero is a matter of interpretation. https://bitinfocharts.com/bitcoin/