Say this on NeoGaf and have to say this makes a lot of sense, Switch launch feels an awful lot like a "soft launch".
- Not too many third party games, and lots of devs don't even seem to have dev kits yet. Most of big third party stuff will be coming by end of year
- Only 2-3 million units for launch
- OS by all accounts, seems incomplete
- No proper online functionality
- Seemingly no other apps (Netflix, browser, etc) besides core gaming functions.
Even the games when you think about it the first two "major" Switch games are Wii U ports .... Zelda and Mario Kart 8. It's not until summer (and that could be as late as August/September) that Splatoon 2 shows up and even that looks exactly like the Wii U game just expanded outwards.
I think they are rushing the system out for March so that they can have some systems sold for the fiscal year end report (which ends March 31st, 2017).
They'll trickle out some systems, get a little bit of a userbase going, but I don't think the system "really" launches until September or so, when Splatoon 2 will be out and this when third party games like NBA 2K, Skyrim, FIFA, etc. are presumably going to start coming out.
I also would not be surprised if Switch inventory/shipments are supply constrained for a while, probably into September. Fall 2017 I think is when the system actually has it's "real" hard launch, that's when you'll get Mario Odyessy + Pokemon Stars (seemingly), better supply, some better third party content, maybe a price cut (or maybe not), etc.
March is also kind of a random time to launch a system too, I think Nintendo is mostly just going to be aiming at their really core fanbase for the first several months, they're going to be conservative with supply of the system for fear of overproducing.