Question: "I just got back from an interview at one of your branches. The person I spoke with told me to cut a lot of material from my resume, but I think that would be a really big mistake. I have a great deal of specialized experience. I think that's really what's going to make me stand out and prove my value to future employers. How can I stand out if I have the same one page resume with generic, non-specific bullet points that everybody else has?"
Answer: First, to your broader point of does my Account Executive know what they're talking about, yes. They do know, and it's in your best interest to trust them about this kind of thing. Your Account Executive has worked very closely with their client companies to develop a detailed understanding of what those specific companies are looking for. If you are being asked to modify your resume it's only because your Account Executive has determined that is what is needed to give you the best chance at getting that job. We're all working on the same goal here getting you a rewarding opportunity that you will enjoy and where you can thrive.
More specifically, concise doesn't mean generic. You have a lot of experience, and that's fantastic particularly if it's experience related to the position to which you are applying. However, don't think of your resume as a place to record every single thing you've done throughout your career. It's actually intended to be a brief summary to get you an interview where you can talk about your specific accomplishments in greater detail. Think of it as an advertisement. Most advertisements only run 30 or 60 seconds. You can bet that all of those advertisers have a lot more that they'd like to tell you about their product. But, they all understand that their audiences' time and attention is very limited. To goal of the ad isn't to sell the product. It's to introduce you to the product and generate some interest so that you will want to know more.