You picked the title of the thread.

Also the article uses the words 'lost' and 'discovered.' Hansen's been working that region for 20 years. He already knew they were there.

I first heard about them in a Great Courses lecture series from 2014 which has an entire chapter dedicated to El Mirador and the region around it (edit: plugging because it's really great, Barnhart honestly makes learning fun). This technology has even been used the exact same way in the exact same region before. In 2020. In 2019. In 2018. Barnhart's lecture on El Mirado talks about it (again, 2014). The book 1491 (published 2005) talks about these discoveries.

It's not an accusation. It's common for articles, and the academics who want them published, to engage in some bluster about what they've 'found.' People get more excited about 'new discoveries' than they do about 'we knew this was here 100 years ago but we never shot radar at it!'