The majority of new vehicles being fully electric will happen pretty soon. The economics of this happening are incredibly compelling, essentially inevitable. I would put this occurring before 2025, but it's hard to say. If the Chinese keep up the heavy push toward electrification, it will probably be sooner. If not, then later.
No? Not even remotely close to true. The Model 3 broke into the best selling sedan list. That's great, but it's not even in the same ballpark as an EV taking the top vehicle sales spot much less EVs being the majority of new vehicles.
Just to return to reality here there are more F150s sold in 6 months than Tesla has sold in its lifetime (450k; https://media.ford.com/content/dam/fordmedia/North%20America... vs. 300k; https://electrek.co/2018/02/14/tesla-delivered-300000th-vehi...)
In the first half of 2018 there were 8.5 million vehicles sold in the US alone. The Model 3's accomplishment of 40k vehicles is a rounding error.