How does a generalist go back to being a specialist?

Companies who champion specialists are half-hearted about hiring a generalist. That's what I think based on a recent experience with a hiring manager. She was looking for someone who has technical knowledge. Technical knowledge akin to an engineer. Strange, I told myself. This is the first time I have heard of this requirement. Further, she questioned my abilities given that I don't have an engineering background.

"How do you cope?", she added.

I reeled off my experiences, trainings, further studies and so on. Yet she doesn't seemed convince. She hinted another position which I have no interest whatsoever.

The headhunter told me that I'm scheduled for another round of interview with the department manager. I don't want to be negative about this prospect but I'm not keeping my hopes high either.

I've been a specialist and generalist in the past. I see it as an advantage because it allows flexibility in switching from being a specialist to a generalist and vice versa. Or so I thought.

Having an engineering background does not guarantee that the appointed person would hit the company's targets. In the past, I've sold products which are heavy on corporate legal affairs and I was able to breeze through it. And I am not a lawyer.