It is not simple. Being assigned a heading or an altitude to maintain is a clearance, if complying with that clearance takes you into the bravo, then it follows that you have been cleared into the bravo. I am aware that that is not the interpretation in Doremire. However a reasonable person who has not read that decision could easily come to that conclusion, as it seems the OP has. It is the responsibility of ATC, having provided a clearance, to ensure that that clearance is safe. It seems to me that if a pilot was violated for a situation like this, that they would have solid ground for an appeal, and that the only instance where a pilot would be reported in this case is if a loss of separation occurred due to controller error and in an effort to cover their own ass, the controller turned the pilot in. It is akin to the ridiculous visual separation phraseology that has gotten so many controllers violated that a lot will not even use visual separation at all anymore.
As a controller I sure as hell would not issue a vector to an aircraft toward any sort of ATC assigned airspace and expect the pilot to turn to avoid the airspace without having first been released from the assigned heading. To be clear, 'advise you turn thirty degrees right for traffic' carries different connotations than 'fly heading zero niner zero vectors for traffic'