While PHP_CEO might be distracting entertainment, some of the best accounts, including the ones mentioned on this thread (@StartupLJackson, @SwiftOnSecurity, @internetofshit, etc.) are not parody but satire, which is definitely a worthy use of the medium.

I mostly follow scientists in my field, which is a good way to hear about developments that are relevant but slightly adjacent to my specific interests, and also the politics of science

Mostly. Some of my favorite accounts from before I quit:

https://twitter.com/onetweettony

https://twitter.com/stealthmountain

https://twitter.com/needadebitcard