I remember when this was a huge thing back when Chrome was really new.
Other browsers always needed admin permissions to be installed and to be updated at the time. Chrome installed by-default in the user context, didn't even ask for an installation location (which sucked 😅) and could also update without adminstrative privileges.
Of course, nowadays this is entirely normal. But while it wasn't the the first software to do it back then, it was the first one where the average user say something being done without a popup about changed system settings.