With all that said, applications back in the day being talked about were ridiculously easy to crash, and in the early MacOS and Win3.1 days, I mean the entire computer to the point of hitting the reset switch.

This and a huge amount of size in applications is features and libraries that allow compatibility between all kinds of different formats. Being able to open and convert almost everything is a boon, while also being a security nightmare.

Lastly I bet a lot of these applications could be way smaller if a lot of the UI prettiness was stripped from them.