This is literally just sugarcoated PR corpospeak which Itsuno does a lot. We know exactly what happened with DMC4's development and why they didn't make DMC5 immediately after from other interviews.

The team was totally burnt out after DMC3 and had zero ideas for a sequel. DMC4 was forced on Itsuno by Capcom and it took a long time to come up with ideas for the game (hence why Nero is totally absent in the first two CGI trailers for the game, they literally had nothing when it was announced). They also struggled with the new MT framework engine and the rising workload of HD game development. The reason he didn't immediately go on to make DMC5 isn't because he thought DMC4 was "perfect", he was literally just sick of it and wanted to make something else, that being Dragon's Dogma. With DMC5 he had several years to come up with new ideas and that's why he was much more passionate about it