Why my switch user button has moved a menu level deeper

You're using a 3rd party Start menu software, as the default one doesn't come with "Switch user", "Lock", "Sleep", and "Hibernate".

Why didn't they add a second button, one for their MS stuff and one to log out/switch user. Show the second button only when you are logged in with a MS account. So much useless space on this start menu.

If ms don't change it, then try openshell for a more traditional menu. In windows settings (taskbar settings>behaviours>alignment) you can also set the menu to the left hand side. I use it with retrobar