It was great for sharing and searching notes, but definitely challenging.
Once in a while when a diagram was needed it would be really challenging to do (no stylus or touchscreen back then), and when a new math symbol showed up for the first time it would be a challenge.
In other times it could be useful, like if there’s a lot of matrices being written copy and pasting helps.
Overall, it was a good experience since for later math research I needed to know LaTeX well anyhow. But the flexibility of pen and paper can’t be matched.