It's like the ultimate DDOS opportunity- tell everyone to go follow <account you don't like> to drive up their costs to bankrupt them or force them off the platform. Create bot accounts to follow all the up-and-coming politicians of your opposition party or your startup's rival or the media company with a bias opposed to yours.
Then the arms-race component would kick off, and you'd have secondary accounts retweeting primary accounts to spread the followers over hundreds of alt accounts.
The fun part would be they'd have to place caps so hobby users didn't accidentally go viral and get lots of followers, which in turn would create scarcity for the users who follow the now capped account. Imagine someone bragging they're part of the elite 1,000 first followers of whatever random account is popular at that moment.
All of the large accounts will pay a reasonable fee.
I'd probably pay $10k/mo for my brand if it allowed me to talk to 1M people interested in my products as frequently as I wanted. How much would the same cost me on other platforms? A comparable business is something like mailchimp where you pay $300/mo to message just 10,000 contacts.
And yes, Twitter would need to get better at purging bots, but that is a good thing and a nice incentive to have.
Media and institutions have the budget to pay here.
Free-to-use is somewhere in between: the notable users get compensated with access to attention, and Twitter benefits from the attention-time of their audience.
So, the underlying point that I think you're making -- that notable users get a fantastic deal on social media at the expense of society -- is well taken.
Let's hope that a new mass communications technology emerges to disrupt this dynamic.
Something like
0-100 followers : free
100-1,000: $5/mo
1,000-10,000: $20/mo
...
1M+ : $10,000/mo per 1M
The aligns the incentives and value provided. Someone having 1M followers on twitter has a powerful platform for their agenda whatever it may be. This should come at a progressively higher cost to them (not their followers).