Not the problem but is neither the "golden solution".
I work on an Agile team that because they are agile they believe they can change things, requirements & focus every two weeks. Plus, anyone that says waterfall doesn't work is ignoring ALL *critical* software we depend on. Do you think airplane control systems are developed using agile? Bankin systems? Stock exchange? Power grid... your OS for fuck sake (be it linux, MacOS or the other one).. none of them were fully developed using Agile.
Agile ADDs a lot of good stuff on top of waterfall and is more transparent and flaws/problems become apparent earlier - that's all. It doesn't solve *the problem of sw development*.
I bet you that in 10 years there'll be another *agile* with a different name and book that will promise that THEY are solving the problems. Smart people take agile and try to make it better, dumb people follow it like religion (and like any religious one, they sin).