If you ask me, Master Chief Collection on Switch sounds like an announcement for something big like TGA. If MCC Switch is revealed at any point in time, than one thing's for certain: support for Master Chief in Smash would explode.
Oh, easily. One of, if not the biggest factors in people seeing a character as likely is a Nintendo appearance, and MCC on Switch would do just that. I think that the
perception of likelihood--that is, people seeing a character as likely to get into Smash--is the biggest factor in garnering support for someone. Characters like Doomguy and Reimu have benefit a lot from this; the former appeared on Switch last year, and Bethesda employees have made reference to Smash before. Both characters have appeared in plenty of rumors, likely made with the purpose of garnering support. Steadily, people have seen these characters as more and more plausible for Smash, so they talk more about them. The effect has been a visible increase in demand for these characters, especially Doomguy, the biggest beneficiary of this, because people keep hearing about them being in Smash and how much sense that makes.
If an MCC on Switch announcement hits, Chief's support is gonna spike,
big time. Suddenly this Microsoft character who has nothing to do with Nintendo will be sitting right there on their console, and will effectively be a part of the Nintendo umbrella. As soon as that happens, he'll suddenly make a whole lot of sense to people. And hey, if Infinite turns out to look like a promising game
by some miracle, interest in Halo will be the highest it's been in a long time. While none of this will affect his actual chances of getting in, unless you subscribe to the "must have appeared on a Nintendo console" train of thought, it would be fun to see people seriously anticipating Chief in Smash on a level comparable to the other major fan demands