Not just because it can buy water means it is mainstream because it is a need to be adopted by worldwide and not just in specific place , remember that there are countries now that already having this existing like in El Salvador yet is this already mainstream? maybe in their country but worldwide is something we still waiting.
People aren't buying water bottles with Bitcoin in El Salvador or anyplace else. You don't need a government to buy up a bunch of it like they did in order to make Bitcoin mainstream, you need to make it perform comparable to credit card transactions at a comparable price, which Bitcoin is at least 1000x from being.
The water bottles was used as an example to represent basic items. Well, people might not be using Bitcoin to buy a lot of their basic items, probably considering the high fees, but when the dust settles, I'm sure many things can be purchased with Bitcoin in El Salvador and beyond. Personally I have paid for many things through Bitcoin even across borders.
Everybody knows the name "Bitcoin" and it's a meme worth over one half trillion dollars. What more do you want?
I disagree with you that Bitcoin is a "mem". That is far from the truth and seem to me like FUD. If you have not used Bitcoin, then you will never know the power it carries. If you come from a country like mine where there are several restrictions to FX, you will appreciate Bitcoin better. We cherish Bitcoin here because we know how difficult it is for the average man to do business across the globe even in remittances. So Bitcoin is far from being a meme.