Might be unsafe in the capital, but you don't want to hang out there anyway. Places like San Pedro la Laguna and other villages around lake Atitlan are super safe. Not for a moment I felt unsafe and people walk here at night alone, even solo girls etc. Might be safer than your average big European city actually.
The rest of Guatemala is pretty dangerous indeed, I watched the news with my Guatemalan host family and the things that are going on in the capital are pretty bad. However, if you take private shuttles to commute and avoid dodgy cities you will be fine, and this country is a gem! So many things to explore