So by your count out of 14 chapters six document outdated or overly tricky features of the Perl OO model (5,8,9,10,11,14). while Five are straight forward useful (1,2,3,4,12) ... and one is useful but advanced (13).
By my count that's 35% of the chapters that are directly useful to a Perl5 developer today. Those chapters are also front-loaded. Not bad for a flippant remark.
As for encapsulation, I've listened to stvn's rant about it more than most people. The point isn't that encapsulation is bad, the point is that going out of your way to enforce encapsulation in a language like Perl is simply adding complexity with no benefit. Why double your code when a simple rolled up news paper across the nose is sufficient? "Bad Programmer, No Cookie!"
That said I'd agree with you, I'd rather have a developer who read Damian's OO book for the 1/3 that is *useful* about OO Theory ... and then used Moose ... rather than a developer that doesn't understand OO at all and things Moose is a Magic Bullet. But given a raw programmer, I'd rather have them learn good OO theory using a proper tool like Moose than I would have to re-teach them all the things I had to forget when I moved from raw Perl OO to Moose three years ago.