Yes, and that's pretty much how things work in most Linux distributions by default.
Packages like sudo exist as a convenience to gain temporary access to perform common tasks that require additional permissions more quickly. But traditionally you are supposed to log in into the root user account for that.
The problem is convenience introduces risks, as saw in recent news. But security is not an absolute term and everyone needs to assess whether the risks are worth it or not.
I'd prefer to use a password manager for this, because then the password would be encrypted.
The clipboard is also not a secured place to store passwords, even temporarily, since it can be read by any program. Of course, it might not be a big deal depending on your own use case, etc. But I thought I'd mention it just in case.
Another feature of password managers is that they can simulate key presses for you when used in certain windows, so nothing goes through the clipboard.
Although under Wayland this might be differently, as I seem to remember only the application that is currently focused can read the clipboard. Not sure how that works for background services, however.
But using an external / additional authentication mechanism is always a good idea. Using a Yubikey, for example as mentioned above. Although that needs some configuring, and I'm not sure how that works as I've never used it myself.