So I'm on the webpage version of the eShop at the moment, and having a look through how many Virtual Console games are playable/purchasable from different systems to get an idea of how it compares to NSO:
NES: 0
SNES: 75
Gameboy/GBC: 0
Gameboy Advance: 70
N64: 26
Gamecube: 0
DS/DSi: 31
Wii: 549 (Most of these weren't released as VC, but are simply backwards-compatible Wii games available through the eShop).
Let's have a look at the 3DS (for simplicity sake, I'm including all 3DS family consoles, including the New models):
NES: 0
SNES: 31
Gameboy/GBC: 79
GBA: 0
DS
Si: 745 (again, these are backwards compatible titles available off the eShop rather than being released as Virtual Console)
Whilst there are gaps in both lineups, and NES games are now available where they were not previously, it's still hard to feel like NSO is anything but a massive step backwards from what was previously on offer. Even excluding Wii games, Wii U VC had an offering of nearly 200 older titles, and 3DS was well over a hundred if you exclude the DS games.
Nintendo could have literally set up their own separate digital storefront on Switch for these older games (they could have called it something like the Virtual Console), and they would have had enough content to keep people happy for years. Instead, we've regressed backwards in terms of number of games available, breadth of platforms, and long term support of purchases.