Maybe im a not a fun dm for everybody but I be usually require classes from a published source. I barely have time to play DND as it is and I don't want to worry about balance issues or rules that haven't been play tested. Even of playing DND for 8 years I wouldn't feel comfortable doing it. I just wanna play DND and not have to worry about hurting anyone's feelings on their pet project.
Pretty much. If the DM has a desire and you can work with them on the class that's cool but it shouldn't be expected. The DM puts the time and effort for the session and players should understand that.