I do actual work on my laptop and I certainly don't need a 17" model. Those days are long gone, and given that apple wasn't making enough money on them (Why else would they kill of a product), we'll not see a return imo.
I think what might have changed is the fact that, spec-wise, the 17 inch laptop wasn't any different than the 15 inch. They've said that they're running into limitations on logic board/battery size when upgrading to DDR4, so releasing a meaningfully more powerful 17" with either better battery life, improved components, or both would fill a niche that people are looking for.