If you want stability above all else, sure; tricycles exist and are more stable than bicycles, and you can go up to 4 wheels, too. They have other downsides, ho

If you want stability above all else, sure; tricycles exist and are more stable than bicycles, and you can go up to 4 wheels, too. They have other downsides, however. More friction, more width needed to both travel and park, and actually worse stability when cornering at speed (they can't lean, so are at risk of flipping in a turn). Cargo bikes often have more than two wheels, but people who don't need to carry significant weight in a basket tend to prefer bicycles as the more practical option. Parents in Copenhagen do often choose the tricycle-with-basket at a moderate speed, as a safer option than putting a kid on the back of a bicycle. But that only works when you have wide bicycle lanes.