I worked at Cycorp for 3.5 years, so I can say:
While I haven't been surprised to see Cyc become more and more clearly a failure, Doug Lenat was no grifter. To the very end, he (alongside a handful of others at the company) was the truest true-believer I've ever known. Cyc was his life's mission, and he never doubted that.
Doug was an uncynical person.
I don’t know Lenat and don’t have an opinion one way or another. But be careful suggesting someone is grifting verses just believing in an idea that ultimately doesn’t come to fruition.
Just because Cyc - and symbolic AI in general - failed to scale like DNNs (including LLMs) doesn't mean that its ideas were all bad.