I would say, in a martial sense, no-one could argue that martial arts have not gone downhill post WWII.
Remember, the nature of them was changed.
On the other hand, Aikido is a postwar art, and it's principle was not martial, but 'peace'.
Sport, money and ego are now the battlegrounds of martial arts, whereas, before, the battleground was the testing place for the effectiveness of all arts.
The old ways are gone, now. Taking the sign from a dojo, challenging instructors etc are just tales to be told.
From my own point of view, I believe that (maybe unintentionally,) the purpose of a MA is to develop a society, not an ego or reputation. It is about growing up.
In a modern sense I think that some martial arts don't contribute to that evolution in a person.
From aikidos point of view, I would have to say that (,this is a quote from an old instructor,) a lot of yudansha are confident, not competent. This is not to be disrespectful, the same can be said of many arts. O-sensei didn't create aikido to beat other people remember...