By no means am I calling the product perfect. Resource hogging is an issue that is particularly important to most HN users.
But would you say that they're _not_ investing in the product? They're improving on search, their API, adding new integrations with Github, etc. Those might not be the things that matter the most to you or other HN users, but they are investments in the product.
Yep, use it every day. Agree that it takes a lot of resources. But lack of investments in one aspect of the product doesn't mean that they haven't / aren't investing in other aspects.