If you're using your personal MacBook or MacBook Pro, it's probably got less memory and storage than your work machine to begin with, so it's even more important to keep the clutter at bay.
In a lot of small and large ways, you're on your own. And while the corporate IT team is still reachable, you can no longer just bring in your machine for them to clean and tune up. But now, for many of us, our home computer is also our main work computer. Back in the 'before times' (before COVID-19 forced many of us to work from home), we often had a work computer and a home computer.
While you could - if you had time and knew where to look - hunt down all your own leftover files and clean them, your Mac doesn't have a built-in way to find and remove this waste. New updates, uninstalls, extra translations, and ongoing usage create digital detritus that takes up precious storage space while bogging down performance.
Even if we're super-fastidious, our computers generate their own junk.