Approval of ETFs will take some more time but not too long.
But I guess its inevitable.
I think it won't be accepted in the next one month for example because we still have a lot of ways to go however I do not believe it will be later than 2020 neither. Hence, anything between 2019 and 2020 would be a wise assumption, it will during the year 2019 but when it will be I have no idea, depends on what the SEC looking for in an ETF before they accept it.
Yes, I won't see SEC accepting it this year, perhaps in the next 1-2 years when they have grasp how this market works and how "manipulation" can be reduced then that's they time we might see them giving it a go signal.
If it is the demand than we can be assured that there is a huge demand for a bitcoin ETF and we will eventually get it however if it is "would having a bitcoin ETF affect anything" then we might have a trouble because even though all the speculators here talk about how having an ETF would change everything it probably change anything for neither us the bitcoin people nor for the ETF investors because there won't be a much change, ETF won't affect bitcoin directly so it won't change it at all.
Demand will definitely go higher as SEC's approval can be look at adding some form of legitimacy so investors are willing to pour their cash. I think Wall Street's are just waiting for this big news and once its approved, it just a matter of time for huge investors to come in and make the most out of this market.