I noticed one of the captions mentioned it was a Kodachrome slide, and I found this website which has old photos and searched for Kodachrome slides (note I have ublock on, I think the website might look pretty terrible without it):
https://flashbak.com/?sfid=369046&_sf_s=Kodachrome%20Slide
A lot of them have the same vibe color grading-wise, I think it's a kodachrome look.