There's a number of concepts here, that are common in the security world.
Firstly, we always want users to run with "least necessary privilege". The idea, especially in an enterprise environment (I'll get to this bit later), is that we want people to have the permissions they need to use the computer, but no more. "Business as usual" (BAU) doesn't require changing files in /etc; that's an exception case.
This leads to the next part; "privilege escalation". Once something outside of BAU is determined, we want the user to be aware they're doing something more privileged. So use the
sudo command and re-enter your password to confirm you know what you're doing. This re-entering of the password is important, because it means that the user is consciously approving this action. It doesn't necessarily have to be a password, either; there are versions which can require 2 factor authentication, that will keystroke log your session and record it for later playback...
So now we come to "enterprise" and we look at the lessons from Windows XP Home Edition. In that, the user you created at installation (or first-boot for OEM) automatically had admin permissions. You always ran as admin. Which meant that any mistake you made might delete critical files. Or any of the bugs (eg in email, or image rendering, or...) that allowed an attacker to perform actions automatically had admin. This is one reason why viruses and malware ran rampant in older Windows versions.
So the separation of "BAU" and "privileged" activities extend beyond the enterprise and into the home, and into the single-user environment. It's worth noting that from Vista onward even Windows has the concept of "you're trying to do something privileged; re-enter your password".
sudo is just a way switching security contexts; from activity you could reasonably expect to do every day ('read email', 'create a document', 'browse the web') and stuff that is considered privileged ('create a new user', 'change system configuration', 'delete files owned by another user'...).
For most home users, just having the "re-enter your password" is sufficient. For an enterprise things can get a lot more complicated; see https://www.sweharris.org/post/2018-08-26-minimal-sudo/ for an example of some of the concerns.
EDIT TO ADD:
I should also point out that Unix also has the concept of an "admin user"; this is the "root" account. In an enterprise environment we don't like people using this because we don't know if Tom, Dick or Harry have used the root account to make changes.
sudo is a way of allowing people to escalate their privileges in an auditable least privileged way. Tom can run
sudo cat and read any file but can not reboot the machine; Dick and Harry can
sudo reboot to reboot the machine but can't read protected files.
In this way
sudo allows for minimal privileges needed to fulfill a role to be assigned. Which is a key security requirement.