Lindzen retired only in 2013. I don't see how this makes his opinion about CAGW less valuable, especially given the fact that he was skeptical about CAGW hypothesis for a long time.
"Judith Curry also used to be a scientist and quit her academic job; presumably being a shill pays WAY better." - where's the proof that she is a "shill"?
Roy Spencer is a renowned scientist in my book: "Roy Warren Spencer is a meteorologist, a principal research scientist at the University of Alabama in Huntsville, and the U.S. Science Team leader for the Advanced Microwave Scanning Radiometer (AMSR-E) on NASA's Aqua satellite. He has served as senior scientist for climate studies at NASA's Marshall Space Flight Center."
Again, where is the proof that he is oil industry's shill?
Does it automatically make CAGW hypothesis wrong? Does it make their skills and knowledge in climate science less valuable?
I was speaking specifically of Spencer, and, yes, it calls into question everything he professes.
"Shills" is an insult, not an argument.
So, basically, yes, they are all bought and paid for, or, they simply have no credentials or knowledge of the field in question.