To be fair, emailing binaries (apart from known types such as images, PDFs, etc.) is a rare enough use case for legitimate purposes and an easy enough way of spamming malware to clueless random people that it's probably a reasonable default for gmail.
Having an option to allow them might be okay though. (I barely use gmail so I don't know if it has one or not.)
For not sending binaries by email - there is no shame to being young in this case as it means never developing the bad habits.
Before Dropbox and similiar it was far more a norm and various file sharing systems like SharePoint may wind up not actually used. Non-computer technical people often do so in companies all the time and practically use it as an ersatz version control system to the cringe of IT.
Having an option to allow them might be okay though. (I barely use gmail so I don't know if it has one or not.)