Probably already been said but,
The problem isn't that Ubi are doing this, best of luck to them, it's the fact there are enough smucks in this would to make it worthwhile for Ubi to be doing this. I mean, jes, come on people!
When I come to playing the game, if the microtransaction system actually has a negative impact on regular gameplay and advancement I'll stop playing completely and that'd be the end of the AC series for me.
I've no problem with Ubi doing this, and making as much money selling snake oil as they can, so long as the end game is fullyplayable to completetion without being forced to use microtransactions to bypass artificially slow progression.