You may be surprised to learn that removing admin rights is no longer (and never really did) protect against app installs. Many developers have figured out they can just install into the user’s profile.

Only apps that truly need admin rights (that install services, etc.) would be blocked. Everything else is wide open.

The admin rights restriction on app installs was almost just a convention that people followed. Now that the app incentives have changed (malicious apps don’t try to take over the machine anymore, they just try to steal your data), admin rights restrictions are becoming irrelevant.