So called "clipless pedals", although invented in the late 1800s and further developed by Cinelli in the 1970s, did not become common until LOOK, a company with patents on ski shoe fastening (binding) systems, developed their product in 1984. The LOOK system is still popular today.
Next on the scene was Shimano who created its SPD system. This used a smaller cleat that was able to fit into a recess in the shoe which in turn meant that shoes were able to be both cycling specific and ok for walking.
People often have a moment of fear when they first use clipless pedals. They might worry they will get stuck to the pedals and fall off. In fact it is extremely easy to disengage and people that talk about there being a problem are likely to not be speaking from direct experience. True, there have been a few falls. But most cyclists just brush the issue aside.
Cyclists like the added safety afforded by the clipless system. When they are standing up and turning to look behind there is no chance of their food slipping off the pedal. In the cities, unless the you confine yourself to bike paths, you are going to ride with traffic to some extent. As you filter into and across lanes, you need to turn around as you are about to make your move. Being secure on your pedals is something you really want.