Clearing Systems Data?

https://preview.redd.it/ctxvz24t2cie1.png?width=936&format=png&auto=webp&s=478f01374bf06b6de1aa05a2622151fc01145b90 I have 100 GB of storage taken up by systems data, what does this mean and how do I clear it? Already cleared system cache, system logs, uninstalled apps, and got rid of unused languages. I do not want to use a paid service to fix this unless I absolutely have to. TIA!