A totally different line of reasoning why you should use jspx instead of jsp:
JSPX and EL makes including javascript and embedded java codes much harder and much less natural to do than jsp. EL is a language specifically tailored for presentation logic.
All this pushes you towards a cleaner separation of UI rendering and other logic. The disadvantage of lots of embedded code within a JSP(X) page is that it's virtually impossible to test easily, whereas practicing this separation of concerns makes most of your logic fully
unit-testable.
