A pound a year won't do much if anything to stop bots, all it will do is slightly up the cost of hiring them given that just setting up a bot farm is reasonably expensive to start off with.
Remember since Musk started doing his "enter credit card for verification mark" stuff there has already been a huge surge in bots and scammers who are quite willing to pay $8/12 a month for verification, and even a fair few that are willing to pay the $1k a month for the "verified organisation or company" marks.
What a charge will do is push away a lot of users who are already getting fed up with how twitter is being run.
I guess my thought being that bots don't last long, so if they keep having to pay £1 per year, but only get 1 week from that bot, it's going to cost them £52 per year, per bot etc.
I imagine as well there are different types of bots. Ones that are there to get money out of people, so happy to pay the price to appear authentic, and those that are designed to cause disruption, and make someone like trump appear popular, or make every polltician look bad and dirty so that those that are really the bad ones get lost in the noise. Those bots paying a small £1 per year can rack up, and on top, there surely won't be that many credit cards to keep bots alive.
