Feelings be damned: results matter in business. Passion, sweat and effort don't mean shit if you don't produce.
You're more or less correct, but it's a tough situation. Games can not come together for so very many reasons. Usually it's nothing to do with an individual person's talents, or high level vision, or even the team. Playtonic has a great team, there is zero doubt about that.
They longer you work on a game, the technically harder it becomes to change things. And sometimes design problems don't reveal themselves until it's often too late to fully turn around. So sometimes even a great team with all the best ideas, intentions and skills, can find themselves in a tough spot that makes it very hard to just work your way out of. Everyone in game development experiences this on a regular basis. Everyone.
Working your way out of something can be done, but it's MUCH tougher, especially when money is an issue. It's easy for Miyamoto to say "a delayed game is eventually good". He has Nintendo backing him.
What I can also say is that if Yooka Laylee (or any game for that matter) is bad, good, or simply average, the developer already knows it in their heart. All they can do is make the best of it, share their creation with the world and be proud of their incredible achievement of shipping a game. Because no matter what faults of Yooka Laylee become evident when the reviews surface, making this game would be fucking hard and the team should be immensely proud.
But yes - the reality is, only the greatest games deliver results and passion doesn't pay the bills. Sometimes it just doesn't work out, even with the best team, the best concept and the best intentions. It fucking sucks when that happens, and I really hope it doesn't happen for Playtonic. Regardless of the outcome, they deserve mad respect for their work.