Unfortunately, there's been a lot of talk about how lots of these tickets ended up in the hands of scalpers, and how the scalpers have even been threatening fans trying to get tickets. More dates aren't going to help fans go if someone doesn't do something about the scalpers (obviously not Taylor's fault, just clarifying!).
But it's incredible how much demand there is, I'm sure she could sell out even more dates too. Makes me wonder how big the European and Australian legs are going to be when they happen.
It's hard for me because the earliest they start is 1am UK time (and the timezones will only get worse as she goes towards the west coast of the USA) but I often manage to catch at least some of it - e.g. the Lover set. It's only like 1-2 times I've stayed up for the whole thing though. When the European dates come I'll be watching everything for sure!