Yes—if Lightroom shows everything is fully synced, the safer way to reclaim space is to let Lightroom manage its local cache rather than deleting folders manually in the OS.

Use Lightroom’s Local Storage settings and reduce the amount of space reserved for local copies/cache to the minimum you want. After Lightroom finishes syncing and is restarted if needed, it should purge local files down to that setting.

Avoid manually deleting folders inside the Lightroom library package, since Lightroom manages that storage itself and manual removal could cause confusion or require Lightroom to rebuild data.