Twitter's mMAUs (monthly Monetizable Active Users) stands at 450 million. If they pay $8 per month, that gives Elon $3.6B per month. It will take 13 months to make $44B - the purchase price QED. Elon Musk is a genius.
From $20 and then dropped to $8, and it is facing a lot of backlash from users. I think if he really applies that fee then people won't pay to stay, they're willing to quit this social network and find another. Social networking is not a monopoly, it is facing stiff competition and we have a lot of free social networks. Although twitter is the most popular social network, that does not mean it cannot be replaced.