This mentality of "oh if you train biceps in isolation, you're a bicep monkey" or "just train arms on a heavy back day, if you have to do biceps for anymore than 2 sets on their own separately, you're doing too much" really annoys me
Everyone is different. And besides that, it works. It's not overtraining, it's not only what bicep monkeys do, and it's not a waste of time
If you can get away with only getting biceps work done through doing bent over rows and chins, fair play to you, excellent, but not everyone is like that and that certainly isn't enough for me.