It's frustrating when WDWMagic users go out of their way to belittle the jobs of the very people that make the WDW run. Yay.
So here's a different, less cynical perspective on the WDWCP.
The truth is that the experience and what you get out of it varies from person to person. Participants doing quick service foods, custodial, some merch positions, etc - are probably not going to enjoy their jobs much unless they're huge Disney nuts who are just happy to be there. Others, like attractions operations and entertainment, may absolutely love their jobs. A CP working at Kilimanjaro Safaris or Rise of the Resistance is going to have a hell of a lot more "wow" factor from their experience than someone who changes trash bins. It also helps if you are sociable and take the opportunity to meet lots of people and network. These factors are why some people leave and never return and others rave about it forever.
Is it a resume builder? If you're 18-22 and your only work experience is stuff around your hometown and/or college, then yes, it is.
Is it a path to a professional internship with Disney? If you perform well in your role, network, and know what you want, you have a better chance of being accepted for a professional internship.
Is it a trap? Well, that depends. Lots of participants have such a great time on their program that they decide to move to Orlando and work full time. What they quickly find is that living here and depending on the job for support rather than as an activity of sorts on the CP does not carry the same level of adventure and fun as the program, and the jobs quickly become more of just a job. Also, while some folks do get lucky and move up quickly, for every person this happens to, there are many more that stagnate for years, and before you know it, you're in your late 20's still doing the same level of work you did on the program.
So to me, I do feel the program is a valuable "real world" learning experience and a great, memorable experience in general for most participants. Just, try to avoid the trap of wanting to relive that feeling for years. Use it as an experience builder and/or a stepping stone to something bigger.