If they don't read terms and conditions, they may get a problem someday coincidentally. The rules will be different between one to another so they should takes time to read and understand before they deposit. That will avoid from the trouble so they can play gambling without worry.
KYC is just a matter of time so they should be aware of that and don't commit something suspicious as that can attract attention of the casino investigating you. If you don't commit anything suspicion, you will not have to worry with the KYC and even casinos asks you to do KYC, you will not have a problem.
It's important information to read but people can save their time by using a clever approach.
They don't have to read all things in ToS for finding necessary information but they can save more time by searching in the ToS with key words about things they want to find information for reading. Like they can search with KYC, deposit, wagering requirement, withdrawal related terms. This clever approach will help them more quickly finding necessary information they want, save more time so that they can feel more comfortable with reading and spend more reading time for most important terms.
Only the important thing they should read avoiding the misunderstanding from the TOS. You give the thing that gamblers should read but unfortunately, not many gamblers understand this but underestimating. They thinks that the rule have the same as others but there is some points that should be different.
Without reading the TOS, they can get in trouble and they might just accuse the casino scam them but the mistake comes from them without they realize.