A point to consider - both the Vita and Wii U were DOA systems that didn't get a lot of support after their initial period. As such, the value of games for the systems tended to drop faster than normal, especially for a Nintendo product. I'm sure the prices you paid for Rayman Legends were, in part, due to these context.
The Switch, on the other hand, is selling like hotcakes and sales on its games have been few and far between...at rather modest discounts (if at all...they are often excluded from sales). It's possible that this is just another manifestation of the first-year effect, but I don't recall seeing it quite so pronounced for other systems in the same comparable timeframe. For what it's worth, this observation is coming from someone that's been fairly closely attuned to the video game market since the mid-90s.
I'd guess that few Switch games will bottom-out at/near the same level of other 'clearance' software, especially the quality and highly-reviewed products like Rayman. With this in mind, I could justify spending $16 for a portable title - it probably won't go much lower for a physical copy.
TL;DR - I picked up my copy and I'm sure I'll get $16 of enjoyment out of it.