I don't think any of you understand where 2view came from. It was a play on words of the term "2hu" which was originally a deformation of Touhou. On /jp/ before it became overcrowded with generals from /v/, /a/, and /mu/, it was common to refer to Touhou characters themselves as "2hus". People would start threads with phrases like "wich 2hu wud u fug" etc.. Fastforward to when vtubers started popping up, anyone who wasn't mainstream (at least on /jp/) would get referred to as 2view regardless of how many views they actually got. In a way, 2view became an endearing term because there are so many damn smug elitist hipsters on /jp/ that they like to proudly show off how unpopular their oshi is. It's not some mathematical formula or tier system. If you use any number other than 2 in it, then it throws off the obvious rhyme of the phrase. Not only that, it also shows off that your a Twitter tourist that doesn't even know about 2hu and should go back.