Did they use the word (bold) specifically? If yes then you have successfully changed the mind of a doubter. I am pretty sure your teacher heard about bitcoin before your presentation but it was not good thing about it.
It doesn't seem like she had heard about bitcoin before, may be she had but had no good idea about it. I have tried my level best to present what bitcoin is in reality despite all the fud going around. It would be a good discussion if the class was on any finance related subject.
And that's not false, you *can* win. You likely won't, but every lottery can be won, at tinier chances. Not really off topic as the discussion is whether or not that's deceptive marketing and I agree it is on a certain level. It's a matter of language in the end, the subtleties of "can", "may" and "will" at least;)
The sentence doesn't say you can win rather it says WIN only which clearly indicates a deceptive method to attract noobs.