I am no-where near as concerned by this as I was a year ago, when I was expecting the axe to fall at any moment before the Chinese labs achieved some sort of escape velocity. I now think it's too late, all the cats are out of all the bags, there's no moat except maybe a temporal one of a few months, the genie is out of the bottle. There is no secret sauce the US labs have that the Chinese ones don't, or won't have so…
Harness engineering is a moat. There’s user loyalty and reliance on the chassis that Claude is on, for example, just like there’s more market share by MacOS+WindowsOS over Linux Open Source.
If you had said "marketing is a moat" then yes, I would say you were right. But creating a harness equal to or better than Claude Code is trivial. The CC harness is actually shit. There are tons of open-source harnesses than work better than CC while using Opus via OpenRouter.