SEO Service Added Internal Links - Articles Now Read Like Crap, Keep?

I hired an SEO service to improve a site. Before the work, all pages were Yoast green for readability and SEO. The SEO service added huge amounts of internal links to the articles by adding random sentences that contain internal links. The articles had internal links previously, a few each article. The problem I see now is that the articles don't read well with these random sentences in each paragraph.

I am looking for advice. This is a long term project, not churn and burn. My sense is I should delete the sentences with non-relevant internal links. Then I could go back through the articles looking for more opportunities for relevant links. In your experience, to fix a problem like this, what works best?

Also, the SEO service added non-relevant (to the article) key words to the meta description, focus key word and SEO Title in Yoast. Should I keep those or go back to only article relevant entries?