Elon Musk:

“To address extreme level of data scraping & system manipulation, we've applied the following temporary limits:

– Verified accounts are limited to reading 6000 posts/day

– Unverified accounts to 600 posts/day

– New unverified accounts to 300/day”

Source: https://pbs.twimg.com/media/Fz94eReWYAEhkHS?format=png&name=900×900

Source (backup): https://i.imgur.com/WvwtHez.png