Sure. I wouldn't disqualify someone for being ambivalent towards what we're working on, but the person who seems interested is gonna be better to work with.

Likewise when looking for a place to work, if the tangibles are equivalent I'll prefer the place with better intangibles.

I'm not in HR or management, so I don't care about cost effectiveness or productivity beyond "not screwing me over". From that perspective, it's generally nicer to work with someone who finds it interesting than with someone who doesn't.

There's no point asking "why do you want to work here", because the answer is obviously a combination of money and benefits, and how food and healthcare keeps you from being dead.
I can't fault an interviewer who's clearly trying not to ask the obvious question and instead actually ask how the candidate feels about the work instead of disqualifying them for not volunteering the right answer.

It's not unreasonable for an employer to ask a candidate how they feel about the work anymore than it's unreasonable for the candidate to ask about the working environment.