I imagine Playtonic learned a boatload about developing for Switch: that can only be good for Switch owners!
They also indicated that they have been listening to tons of feedback, if we couldn't already tell by the post-launch patch. I hope they have lots of good stuff for the sequel. It does seem they are already well into developing another game, if not even several more. That may well be why it seemed NOTHING was happening during Switch development: it wasn't that they had everyone working on the Switch port, it's that they only had a few team members reserved to keep doing Yooka-Laylee while the others were hard at work with new games. At least, that's what I get out of it all.