Recently, in a discussion on a fitness-oriented Twitter feed about health/longevity gurus whose appearance hasn't aged well, Sinclair was mentioned as an example. FWIW, of course. Paleo guru Mark Sisson looks great, but he's always kept extremely fit (former athlete) and he's on TRT.
I recommend Sinclair's book, which incidentally is quite readable, and you guys dismiss it without reading it because you know it's too much for his kidneys and because someone on twitter might have mentioned that he didn't age well? If you look at his photo and videos online, btw, you'll see he looks quite boyish. Unless you're focusing on one of the other David Sinclairs on the image page for the name.