Okay seems like nobody is RTFA... The average age of participants in the study was over 70, so these findings apply only to the elderly. And the conclusion is

Okay seems like nobody is RTFA... The average age of participants in the study was over 70, so these findings apply only to the elderly. And the conclusion is not that “exercise is good”; the authors were actually trying to figure out if HIIT or moderate exercise was better. TLDR: HIIT is better