By all accounts what he did worked. The potential to end HIV is huge. The amount of human suffering that could be reduced by rolling out what he did is very real.
The technology is here. It's better to strictly manage it for the public good than to lock it away.
Per the wikipedia page it states that it is not clear if it effective because they're not going to intentionally infect the children to test it. But we see the results specifically on the targeted gene. That's a success and demonstrates the technology works.
I'd argue the folly was inserting an artificial gene as opposed to the natural gene that we already know works. Either way the technology showed expression on the correct gene, that is a success.
We'd be having a better discourse on this if his results weren't banned from every journal and not studied.