Ditto. A colleague called into question an off the top of my head estimate. A 2 day estimate and tried squeezing me to cut it down more... For work I wouldn't even be doing. Nope. Not going to do it. I tried to call into question his estimate of how long it would take for one of his sales guys to sell the lead he received yesterday. Once he threw out a number I asked why so long? Needless to say the conversation didn't end on a good note. Live and learn. We'll talk it out tomorrow. A quick way to lose trust and respect is implying incompetency and squeezing/trying to manipulate people. Really kinda pissed at him right now.

The problem is that product and dev are different people. Product managers don’t understand their product as well as the devs do. devs should manage the product definition and work with feature requesters at a very high level, where the details are the choices of the devs (or senior devs acting as product managers.)

you're not alone. I would say that lack of trust is the norm not the exception when it comes to software dev teams :(