All of that info is not true. They do not become more aggressive as they mature. Now some may, as some regular dogs may be aggressive in a certain breed, but are all of the???? The answer is no.
I own two very high content wolfdogs, which are 3 and 4 years old. Neither have displayed any signs what so ever of WWS (winter wolf syndrome) which is what he is speaking of during breeding season.
If you want to talk to more wolfdog owners, you might want to check out this forum and ask questions there, there's tons of owners there
http://wolfdogforum.com/forum/