If a casino breaks their Terms of Service, it is not good but a trusted casino does not do that. If we as customers, don't read Terms and try to exploit their Terms, when casino pull their hammer, we don't have right to say anything as innocent victims.
There might be some casinos who update their terms without notifying the players but the hidden aim of them can be to fool players but legit casinos make players aware about any change and it's also our responsibility to check them before playing and with time also but yes normal playing won't land you into these withdrawal issues.
It's obvious if a casino has motives for unprofessional way like this like implementing a new rule that is widely used or doing by gamblers. One example of this is countries that they ban, all players on that country will be affected immedietly if the casino didn't announce their terms being change in advance. Though most legit casino won't do this since it's unethical. This is why it is important to choose what casino you are playing and make sure that the casino has the reputation that they are protecting for.