There certainly are many naive managers who have no idea what Agile does and how well it works. In a lot of ways, Agile isn't always the best approach to every problem domain, but it is far more beneficial than your comment slams.
In essence, Agile concepts encourage less up front (and as such harder to change) design, and smaller more manageable tasks that can be realistically estimated. Obviously if you slice too fine grained or too broad, you're going to run into different problems. Fine grained slicing, you waste a ton of time setting up component bounds and too broad and you've got the same old monolithic blobs which are hard to estimate and hard to show completeness.
One example, we had a really competent guy take on a huge functional piece of work and spent 3 months bashing at it. We had faith in his brilliance, so he was almost entirely left to himself. Months later, we find that he wrote most of what he did well enough, but it didn't integrate well with the core system. Further, much of it was forced to be rewritten to actually integrate properly with the system. If we had properly managed him with Agile methods (we were using verrry loose agile), we would've divided the huge task into pieces, ran into the same problem earlier and ideally corrected the design decisions before it burned us badly later on.
In regards to your 'not entire systems knowledge' problem, this is a development style, not a learning and interaction style. You're dividing WORK to be delivered. The second you have 2+ developers on a project people stop knowing the entire body of work. Agile neither encourages nor hinders one's desire to learn about all the pieces of a system. True, you have one discrete functional area to work on, but if you're telling me in a pre-agile world you never worked on anything specifically, I'd say people are wasting a lot of time constantly learning and re-learning functional areas when they should be far more effective specializing in areas they're good at and having a general understanding of the surrounding areas in case they need to integrate / change roles.
I feel that you're not happy with your company in general and this is yet-another reason to bash them. Maybe they really are doing Agile badly and you should consider giving -constructive- feedback instead of bashing them on Slashdot. If the company is really making you so angry, you may want to consider a job change. Its better to jump than sit and fester in a job you hate. Trust me, I've been there too.