You could also say btw that GlassFish doesn't need any WebSphere or JBoss. Or you could say that WebSphere doesn't need a JBoss or GlassFish.
Also, WebSphere is legacy within IBM. Their new and much much better server for some time is called Open Liberty. It uses some components from WebSphere, but in a highly modularised way, and the overal runtime is totally different.