My regular biking buddy had rheumatic fever as a child, has had several heart surgeries, is on oxygen 24/7, and rides an ebike. Prior to his health decline, he rode thousands of miles on a non e bike including one coast to coast ride and across Alaska. His riding skills are excellent. As a previous poster noted, it's not the type of bike so much as the type of rider. There are idiots and jerks in or on all sorts of vehicles.