An action movie can be fun without being aggressively juvenile and insulting. I'm not asking for high art, just for something good, and Bay can't even deliver on that.
I get your point here, really, but this is so basic of an assumption that clarification is redundant and needless; it dilutes the message, rather than strengthening it. Poe's Law really shouldn't have to apply here. The idea that when a person states their point of view, they are conveying their personal opinion on the matter is a pretty essential concept of communication, verbal or otherwise.
(If you want an example, take a look at our exchange over Michael Bay. I'm arguing because, hey, it's fun, and I want to convey my thoughts on the matter, but did I need you to clarify that you were speaking only for yourself? Did you feel the need to state "Now this is only in my opinion"? Of course not!)
As for Kafka... he was an author, not a director, but seeing how both he and Bay worked in creative mediums, I figured the connection fit. He was a prolific writer, one unlike any others of his time, and he produced a ton of works. Unfortunately, few were ever published in his lifetime, and he ultimately ending dying in obscurity. The point being, his lack of success doesn't necessarily reflect the quality of his work the same way Bay's enormous success doesn't reflect the quality of his own output.
(Also, are you sure you've never heard of him? The Metamorphosis, A Hunger Artist, the word "Kafkaesque"... none of it ringing a bell?)