Nintendo was never doomed no. Everybody know anything about finacials knows this. But people though they where gonna drop out of the home console race, since they had a snowballs chance in hell to beat Sony. Switch while great (first console i preordered and bought day 1 since PS2) is not a really a home console, but more of a handheld, which is a market they have dominated since the GB.
The direction Nintendo is going now is excellent though, not only did they play 100% to their strengths (handheld market) they finally branched out and released games for anything but their own consoles (mobile games) something they've never done before. I think the future for Nintendo will be bright and since more and more people are migrating to PC, i wouldn't be suprised that the only thing you will be playing in 2 generations (PS6) is PC, mobile/tablet and some form of Nintendo platform.