You use generalities and personal opinion of smokeless just being better. We still do use BP but obviously it made sense to move to smokeless since you don’t have the fouling and can just keep shooting 100s of rounds. BP in trapdoors and sharps rifles is much more than having a smoky experience. There are more factors to try in BP for accuracy than smokeless, the main one being neck tension. Because of all the variables in adjusting BP loads, you can tune one to your rifle better than smokeless load most of the time. So it is worth it doing both BP and smokeless when owning a TD or a buffalo type rifle. It is not just about making smoke.