X suddenly changed the limit on the number of tweets, retweets, and replies that free users can make last weekend. With the latest Twitter Help update, only 50 tweets, 200 replies, and 500 DMs can be sent per day for free accounts. The 50 tweet limit includes RT and QRT activity.
This is a sharp drop from the 2400 tweet limit that was introduced in 2023. At that time, the limit was introduced to combat bots that used X to carry out spam and online fraud. It is not known why this very small new limit was introduced as X has not yet issued any official comment on it.
Free accounts are also limited to following only 400 accounts per day. Once it reaches 5000 accounts followed, another limit is introduced depending on the following and follower ratio.

