The essence of being senior, I feel is "I have made the mistake you are about to make". This echoes in language learning. When I was learning Go I could easily pinpoint what language design decisions were made because of lessons learned from this language or that. (I do not want to suggest schismogenesis applies to programming languages but ... it kinda sorta does?) Teaching with this in mind needs a very different curriculum.

Also, basic exercises are boring because we did them ten thousand and one times already just with slightly different syntax.