Nobody said the contestants had to behave 'like marionettes', just that they were asked to behave in a particular way by the producers to achieve the end result they wanted.
The 'valid comments about being made to look preposterous' were no such thing, they were personal comments about people's characters and appearance. It's pretty rude to make a value judgement about someone's character based on 10 minutes' screen time IMO, and I find personal remarks about people's appearance petty (and predictable!)
I'll apologise in advance for being 'full of myself' and fat. I often ask myself why I put myself through the ordeal of appearing on quiz shows, given that I nearly throw up with nerves before each one! I think after this I might not bother again, so that'll be one 'smug' person less on your TV.