@jeffscott Are you saying that Google already doesn't take keywords into account? Or is it a hypothetical question?
Anyway, I am going to give you my opinion on it. Up until a few years ago, you could rank for a keyword by simply having a bunch of links with exact match anchor text pointed to your page + the usual of keywords & variations in your title tag, headers, and content. However, as of now, that isn't going to happen.
Post Rankbrain, we need to focus more on optimizing for intent versus optimizing for a single keyword. In no way am I suggesting that you don't include your keywords in the right places - those are a must. But as an SEO, we have to take into account the searcher's intent behind a keyword.
Google is smart enough to know what the user wants. It is almost impossible to rank your service page for an informational keyword.
So yeah, wrapping up.. I would say that all the normal factors are still very much in force - links, proper on-page etc .. however, we should definitely try to satisfy intent and improve user experience. I cannot say for sure whether user engagement metrics have any impact on rankings but optimizing for them couldn't hurt, right? If nothing else, it might just improve conversions.