Can men safely take testosterone in their 70s?

Yes!!!!!!!!!!!!!!!!! As long as appropriate screening for latent prostate cancer is performed, then older men can safely take it if they need it. Interestingly there are studies that suggest safety in localized cancer.
I treated 102yr old. Multiple great examples of age related hormone decline is the nursing home population. One of the leading cause of going to a nursing home is the inability to take care of ones most basic needs. Not being able to rise off the toilet or the "I've fallen and can not get up." So, some say treatment is unnecessary or a fad. I guess it depends...
Depends. With all medical therapies, there is a window of opportunity to intervene. This is when the body still recognizes what the missing hormone can do and responds well to it. The longer one has not had it, the greater the risk. Hrt will depend on your health, psa, prostate exam, level of testosterone and other medical conditions. Speak with your physician to better understand the risk and benefits.