I feel anyone staring into just any red light source for 3 minutes a day is a bit dangerous.
Then you better not do any h-alpha solar observing with a P.S.T. or similar as they operated at 656.28 nm and this pilot study used 650nm. I think the rest of us are just fine staring into our solar scopes for 3 minutes and more a day!
FWIW, this study was submitted to the The Journals of Gerontology in Feb 2020 and then published in Jun 2020, which is a monthly journal of The Gerontological Society of America that publishes within its covers the Journal of Gerontology: Biological Sciences and the Journal of Gerontology: Medical Sciences. The publication requires peer review.