gambling platforms usually have chatrooms on their sites, but many gamblers who use chatrooms for spam so the team had to develop an anti-spam chatroom and determine the duration of the chat.
The casino already have a solution for spam in chatroom, here are:
1. Rule for spam will get temporary banned or permanent banned.
2. Hiring few moderators to moderate the chatrooms, they have a power to delete user's reply and ban.
3. User can create new reply after 1-5 minutes from his previous reply.
Most of users are active in chatroom is just to earn rain, raffle or free money from the casino or generous rich gambler. If there's no reward, I doubt the chatroom would be really active because there's no point to have a long conversation on there.