I'd argue the original has lost momentum because the games have lost momentum; the Switch is now a very burdensome piece of hardware to develop for, compared to the other major platforms, and games on it now look and feel very different in most cases to PS5/XBX titles. Once software gets back on track and keeps up with the Jones so to speak, I think they'll be in business, especially with the full backwards compatibility, and the portable/handheld aspect which you cannot ignore, and Nintendo have always traditionally dominated at.
I think you're also missing the fact that most people who'd consider one now have one, the installed demographic for the Switch is currently huge, and they're not screwing up calling it Switch U or something esoteric, like they tried with WiiU, the console this time is clearly what it is, and I suspect if priced reasonably, it'll sell boat loads.
The Nintendo Switch has officially passed the PlayStation 2 to become the second best-selling gaming hardware in the United States, now trailing only the Nintendo DS.
www.ign.com
It's also lost momentum because simply put its ancient at this point in time, most people have been expecting a successor for a few years now, and even Nintendo's internal teams have started to struggle with the hardware limitations - albeit what they've done has been incredible considering its a hardware design from basically a decade ago, the Tegra X1 was designed 2013-2014 era. Kinda amazing what they've done when you think about that.