Exactly my thoughts atm. I'll admit I was extremely hyped for the Switch after the January presentation (I blame the awesome Zelda trailer for that) and immediately pre-ordered it when it became available (plus lots of accessories like Pro controller, carrying case etc.). But to be honest, while the Switch sure seems to be a nice and valuable device, the only games I'm really interested in so far are BotW and Mario Odyssey, which won't release till November/December. So that'd be a 500€+ console purchase (incl. the mentioned accessories and the BotW Collector's Edition) to play a single game (that I could play for a fraction of the cost on my WiiU, even releasing on the same day). The last time I did something similar to this was with the Wii, which I only bought at launch to get Twilight Princess a week earlier (EU release dates). Never again. After finishing TP, the Wii only collected dust for almost a year before it became a video game system worth owning (with the releases of SPM, MP3 and Mario Galaxy).
And while the first year doesn't seem half as underwhelming for the Switch games-wise, I'd rather spend a tenth of the aforementioned sum and just play the near-identical WiiU version of BotW. I gave Nintendo the benefit of the doubt far too often and always regretted it when I bought one of their systems too early in their life cycle (with DS being the worst offender, the first model was just hideous and half-baked).