This is a really good idea ...
... and it's going to completely flop.
Reason being, it's already the third day of February, and people are hearing about this only now. We’re already in the middle of it, so folks are gonna be, like, well, I’ve already spent money on these companies this month, so **** it.
There needs to be a pre-boycott ramp-up period during which people are educated on the concept, learn how to participate, and the date it's supposed to start. It needs to be well-promoted so there’s a critical mass of awareness before the boycott actually starts.
I think this should have been called for at least a month in advance.