How do you know that it's actually faster than if you'd just written it yourself? I think the review and iteration part _is_ the work, and the fact that you started from something generated by an LLM doesn't actually speed things up. The research that I've seen also generally backs this idea up -- LLMs _feel_ very fast because code is being generated quickly, but they haven't actually done any of the work.
Because I’ve been a software engineer for over 20 years. If I look at a feature and feel like it will take me a day and an LLM churns it out in a hour including the iterating, I’m confident that using the LLM was meaningfully faster. Especially since engineers (including me) are notoriously bad at accurate estimation and things usually take at least twice as long as they estimate.
I have tested throwing several features at an LLM lately and I have no doubt that I’m significantly faster when using an LLM. My experience matches what Antirez describes. This doesn’t make me 10x faster, mostly because so much of my job is not coding. But in term of raw coding, I can believe it’s close to 10x.