Honestly, I can hear the argument that the game was coded in a certain way that makes it difficult to port to a more powerful but different hardware. But they could have: either
1) Sold the game for half the price, since Switch users are getting half the frames and this is NOT a power limitation of the machine.
2) Recoded everything. They sell a game FULL PRICE. They should be willing to do the FULL DISTANCE. Moreover, while I'm not underestimating how time consuming the technical aspect is, recoding the game is not the same as redoing the game. The art, the concept, the mechanics, everything is already in place. Had they done that, the price point would have been justified. Currently, it's just not.
3) Be upfront about the framerate issues. This is the worst part in my view. The fact that they waited after the release of the game to acknowledge the problem, and to say that they would not fix it, is downright dishonest.
On switch or any other platform, I won't buy any of their game now. I'm old enough to put my money where my mouth is.