The chances of that happening are really low.
First, the GC had great 3rd party support, even if it missed the most important titles.
Second, SNES support is pretty much equivalent to what PS4 has. Again, it will probably be SNES>GC>Switch/N64.
Yes, we have heard some developers say that they are happy with Switch's sales of their games. We even heard stories on how some sold the best on Switch.
But, considering, Switch already has more than 200 games, what we have heard is really not enough to say 3rd parties are making good money on Switch.
Also, how much have the "big" games sold on Switch? Talking about Doom, Skyrim, NBA, Fifa? Are they selling well or above expectations?
About the downgraded ports... you're speaking mainly about the games i wrote above, right?
Doom was ported because the engine was really flexible (i assume it will be the case of Wolfenstein 2); Skyrim is an old game; Fifa and NBA, i honestly can't say, 'cause i don't remember what i read about them! :D
And what about cartridges prices on Switch? Won't that affect sales of Switch games for those who already own another console?
I've also heard a few comments on how limited Switch is. And if that is true, remember that PS5 and next Xbox are 1-2 years away. Where does that leave "porting to Switch" and it's library potential?