I agree giving prizes for increasing the lifespan of mice is a good idea, but that's not a very strong reason to support him.

Why exactly?

Do you have examples of novel scientific ideas he's had that have turned out to be useful?

The SENS website lists 42 published papers that were funded with SENS grant money. The foundation has a yearly budget of 4 million that it uses to award grants to science that's publishable. A lot of that money comes out of Grey's own pocket and Peter Thiel's pocket. Other money comes from private donations. It's mainly additional money for the subject that wouldn't be there without Aubrey de Grey activism.

Aubrey de Grey may very well represent a picture of aging that underestiamtes the difficulties. However the resulting effect is that now a company like Google did start a project with Calico that's speficially targeted on curing aging.

If you want to convince Silicon Valley's billionaires to pay for more anti-aging research Aubrey de Grey might simply be making the right moves when scientists who are more conservative about possible success can't convince donars to put up money.