I mean, it wouldn't be the first game to show much worse than it plays.
Though I am starting to wonder if Good Feel is just a sub-par partner for Nintendo. This is the second time they've missed a deadline with a fairly straightforward project. Granted it looked very pretty but I see no real reason it should miss it's target date when games like Kirby, Mario, and even Xenoblade hit theirs.
Yeah Good Feel are useless when it comes to productivity, games like this and Woolly World should've taken 2 years to make, not 4-5.
Woolly World was made in 2.5-3 years not 4-5 years, also they had some other projects in same time period.
But what is far more important than deadline is actual product at end, and past 2D platforms they devolped like Kirby's Epic Yarn and Yoshi's Woolly World were very good games (personaly for me they are one of best 2D platformers last 10 years), and I dont have any doubt that this new Yoshi will also be very good game.