Re: Frustrated by unconvincing aikido
The senior person pulling rank was being pretty rude. On the other hand, it's generally accepted that coming to a seminar and doing something other than making a sincere effort to learn what's being taught is quite rude, too. In any case, once you've found out you don't care for the style, it would be polite not to attend any more such seminars.
I would strongly, strongly advise not getting caught up in the idea "How other people do their Aikido influences the value or validity of my Aikido." Since you cannot change how other people do their Aikido very much (if at all) this will just cause you untold amounts of frustration and unhappiness. Instead, rejoice in having a school and style which suit you very well, and enjoy them to the max; and let the aiki-fruities do the same.
If someone comes to you and says "Anonymous, we need to set up a commission to decide which aikido schools shall be accredited, and we want you to lead it"--*then* you need to form opinions on the validity of everyone else's aikido. Till then, you only need to form them on the place(s) you actually train.
(Don't care too much about what the fruities may think of you, either. It really does not matter.)