When you add all kinds of cases, mild to severe, many men have erection issues at some point. In one study, that happened to 52% of guys sooner or later. Most cases were not severe.
Erection problems are often linked to age. For example, they're more common at 70 than at 30. But erection problems are not a routine part of aging and are less likely in men who don't have high blood pressure, diabetes, or heart disease, and who manage stress and emotions well.