Research Highlights: A study of over 20,000 adults found that those who followed an 8-hour time-restricted eating schedule, a type of intermittent fasting, had a 91% higher risk of death from cardiovascular disease. People with heart disease or cancer ...
That sounds like a plausible explanation, but there’s no way to know because there’s no data. As you said, this study is kinda useless.
Not useless, this correlation was totally unexpected, they were expecting to see a benefit. It’s not definitive though, but retrospective reviews like this are important first steps even though they carry many caveats. Now this data could be used as justification for funding and grants for further prospective studies into this to better quantify risks and benefits of intermittent fasting.