I previously worked for a small design/development shop that ended up doing a ton of SEO work and eventually pivoted to selling those ongoing services as a large part of what they did.

It was in no way scummy, nor intended to break search engines.

Our approach to SEO was, in a nutshell: "write quality blog articles relevant to related search terms, include a CTA at the end."

We posted lots and lots of articles. We started ranking very well for long-tail keywords, which we should have--we had the best content available for them.

Nothing scummy about that.