Taboola’s “Read More” feature feature shortens the viewable length of an article and raises the visibility of below-the-article units, encouraging user interaction. This feature generally leads to a 20% or more uplift in interaction with these units, and won’t affect your SEO.
If you’re concerned about how the “Read More” feature will affect search traffic with Google’s mobile-first index that launched recently, Google has stated that features like this won’t prevent the full article text from getting crawled and indexed. Google’s representative Gary Illyes stated at a conference that:
“... content hidden behind “read more” links on a page via CSS will still be able to rank in the mobile-first index.”