Gartner try to influence the IT market. For the dot.com, they succeed, until the balloon explodes. Most of the time they are late or inaccurate. It's likely they live in an ivory tower!

For the IDS part... A IDS are my eyes on the network, like the events log!!! Without it, I'm blind! On the other hand, I'm not sure i will pay the price ask by the IDS vendor, far too expensive. I turn to open source snort.