Google's handling of the title tag has changed over the years and it will likely continue to change so what is accurate today is probably not going to be accurate tomorrow.
Here are just a few of the different ways title tags have been treated OR might be handled in the future:
-Rewarding pages that have the keyword appear first in title tag
-Penalizing pages that change title tag without changing page content (sign of SEO manipulation)
-Rewarding pages with high CTR in serps (which is heavily influenced by user friendly title tag)
-Penalizing title tags that are extremely long (sign of keyword stuffing)
-Penalizing pages with words in title tags that don't appear in site content (sign of possible bait & switch)
The only way to determine what is currently true and what is false is to run some tests.