Reddit investors and advertisers are not spending money on Reddit because of its platform.

That has nothing to do with what a "product" is.

What? So your advice is to knowingly ignore what actually makes your site money and just call some random other feature "the product"? How would Reddit admins/CEOs ever make decisions using that advice?

If you didn't understand what he meant by the distinction between community and product, you should have asked to clarify, instead of just assuming (completely incorrectly) what he meant and arguing based on your own interpretation.

Building up a community and building a product are completely different things. You can have the perfect product yet never get any community. You can get a great community without even a product.

I don't dispute any of those points, but I think it's still silly to talk about anything in terms of "product" that isn't their community. Reddit the software could come and go, it's essentially irrelevant to the workings of the site (barring radical changes). Whatever you call the community of users that's still the thing you have to try and cultivate, the thing you are presenting to investors, the thing that increases your revenue.