Most newbie do not have any idea about Binance. Most of them heard about about coinbase at the beginning. Moreover, fiat availability can be another factor for that. Maybe coinbase pro offer more available fiat deposit option than Binance.
I don't think so. I'm a newbie tho and never heard much of coinbase. Maybe because of the country I am from since we have a major local exchange which have a license with the central bank and no serious competitors that's why most of people here purchase their BTCs there. I am starting to trade now and learning in the process. I mostly heard about Binance and that's where I trade now and what I like about it the most is their mobile application which is very convenient for me along with many other features. I may check coinbase pro out of curiosity and people are pointing out that there are much better options out there with what I have read so far in this thread.