Why disregard someone simply because they own a piece of a company that also supports the goal? I think any rational person would do the same - you believe in something so you start, invest in, or advise a company.
I think the comment also said that this person’s views aren’t taken seriously in the aging research community. So the combination of their ideas and a desire to profit from them raises flags.
I don't think Harvard would let Sinclair have a lab with some 35 people and publish articles under their name if he was a total fraud/quack.
My impression of Sinclair is that he likes public attention too much and often reports on work in progress with too much certainty, but results like this [1] seem to be fairly impressive.
