This is thing I don't understand. I admit, I never used Twitter, but out of curiosity I created mastodon account yesterday and honestly I don't have any difficulty using it, it is very straight forward. Patent poster mentioned scaling issues, I don't observe any delays and apparently mastodon grew a lot yesterday.

Mastodon has short-lived slowdowns on the biggest servers when it’s going through explosive growth, and somehow people spin this into general scalability issues. It’s not a problem in reality.

Twitter went down completely all the time in the early days.