I sailed through 3 years of my undergraduate degree.
To be frank, it was piss easy for me compared with most of my peers who struggled exponentially.
I then took a working gap year and realised that a job is definitely more demanding, but can get tedious quicker than education.
I am now in my spring semester of my STEM master's course and it is probably the most demanding thing I have done since I left high school at 16.
No time to socialise; no time play video games; no time for side-projects; no time to get an active sex life (in my personal case) etc.
Heck, I stopped reading philosophy books for 2 months before Christmas break because I was working on my assignments until I slept.