I work at a big company and these decisions come down from up high. Believe me I would never have picked Struts/JSP.

Actually, Spring is more of a lightweight container solution not a UI solution.

There is no shortage of web UI frameworks to pick from. The problem is that there are so many so it is hard to know which ones will last. You certainly don't want to spend a year building an application based on a certain UI technology and then have that technology die.

The problem here is that you have a lot of people who have been doing JSP's (with a lot of Java code, etc.) for a while so anything that imposes some order is a step up.

I am not a big fan of web applications in general. Complex applications are just not meant for the web, the stateless nature of HTML, and all the roundtrips to the server make it really tough to wite a complex responsive application.