Twitter does absolutely nothing to exterminate old fake accounts. Probably because the last time they did so and saw how many real accounts there were, Twitter's stocks plummetted down
As a NordVPN user I can say that it's not only marketing that they are good at. For example not many VPNs I've tried were as good as Nord in regards to unblocking geo-restricted content. I found Nord quite consistent in that sense. They did have a strange issue with all the servers missing from the MacOS app, but it was literally sorted in 5mins when I reached out to their CS.