X（旧Twitter）、実質有料化へ！無料ユーザーは投稿数や返信数が制限・・・

The current technical limits for accounts are:

Direct Messages (daily): The limit is 500 messages sent per day.
Posts: 50 original posts and 200 replies per day for unverified accounts. The daily update limit is further broken down into smaller limits for semi-hourly intervals.
https://help.x.com/en/rules-and-policies/x-limits