The early ones were, the later ones were beefed up – and no longer 340g.
If I was building/ speccing my own wheels, I wouldn’t have gone this low. I wouldn’t have got ally nips either. But they were a built set, cheap, so I took a chance and, like I said, they’ve been fine so far despite a fair bit of abuse.
But I’m 70kgs and I don’t tend to break stuff. Only things I’ve broken in 30 years have been a rear rim when I spent a few years riding round a campus with a huge amount of step drops to flat between 4-6’+, and a couple of old cranks that had hairline cracks in already. Maybe I’m smooth like silk on a bike, a massive mincer, or just lucky. Tricky for you to tell from there, though.