But that boils down to attitude issues and not so much specific to single pilot or instructors… Unless Airlines start paying up and paying training for zero hour direct entry pilots, then they need to accept the fact that pilots come in all sizes and abilities, Also, alot of training departments are poisoned by the old-boys ex RAF/armed services and as such anybody who doesnt come from same background is immediately labeled.
So there must be reflection on both sides, the cocky CFI who thinks they are the bees bollox in their local pond, and the training department who rubbishes everybody unless they are a fast jet jock or zero hour graduate whom they can brainwash easily.
But if the OP is willing to admit he/she is on new territory and can dial in to the company compass, it’ll be good and the airlines will get a good asset they can use internally for line training etc..