In 2016 I worked on a project about 10 miles from Guanajuato. Beautiful city. We never felt unsafe. Did a lot of exploring at night after work in the region. It was known as kind of being a safe harbor from the drug trouble because it was so deep into Mexico, away from the coasts and US border.
Last year read an article about how the crime had skyrocketed. Garbage bags along the Highway full of dumped bodies. Fun stuff. Our driver carried a pistol everyday. Off the books. Said most of his friends did too.