How do I preserve my workspace layouts throughout all new projects I start? And how do I preserve all my settings when downloading a newer version of Blender?
Open any default file (General, Sculpting, VFX, etc), set the workspace and various settings the way you prefer, then go File > Defaults > Save Startup File. It will overwrite current that startup file.
After an update, Blender usually tries to locate old settings on the first launch and asks if you want to preserve them.
Does Blender also delete the old version after a new one is installed?
I think it shouldn’t? One should be able to keep several versions at the same time.
But if you install from Steam however, it seems to keep only one version (and some leftover folders from previous).