I would hesitate to say yes, so I voted no.
I don't think generations are dead, but with PS4Pro coming next month and Scorpio next year, Switch clearly won't be competing with a truly new generation of hardware for a long time.
With Dreamcast, you had a system announced and launched just a few years before PS2, and had it survived it would have competed with Gamecube and Xbox for several years as well. There was a clear break between Saturn and Dreamcast as well. Until the seventh generation, it wasn't uncommon for the fist console in a new generation to launch several years before other more mainstream efforts. TurboGrafx 16 launch a year ahead of the Genesis and two years ahead of the Megadrive. The first 32 bit consoles were released a year and a half ahead of Saturn and PS1, and several years ahead of N64. Etc.
But Switch will be competing with an upgraded Xbox One and PS4, and will probably be doing so for most of the standard 5-6 year lifespan consoles tend to enjoy. I would, if anything, called it an 8.5 generation console, same as PS4Pro and Scorpio. Although for all we know, generations may truly be dead now.