With Windows I found that clean-installing the OS on my brand-new Dell laptop was useful, as it helped purge it of "bloatware" etc. and get it functioning as smoothly as possible.
Is there any point doing this with a brand new MacBook like this one? And also, is there any point manually updating the computer's software—system-update—upon first using such a brand-new laptop, as is required to do with Windows computers?
No.
Macs come with the OS on a separate volume of the disk. It is read-only, and cryptographically sealed so that it cannot be modified. Only Apple's installers have the certificates to be able to update this volume.
Everything else -- apps that you download, your documents, all your preferences, settings, caches, temp files -- they all go on another volume of the disk, called "Data". (Usually "Macintosh HD - Data".)
As a result of the division, simply erasing the Data volume restores your Mac to a 'factory state'.
There is normally never a need to erase the whole disk and reinstall the OS.
Unlike some PC manufacturers, Apple does not sell space on the disk to third-party software, so there is no 'bloatware' as such.
When you first get your Mac, it will run the Setup Assistant, where you can set up your user account and transfer any data from another computer. Once that's done, you can head to System Settings > General > Software Update, and see if there's a new OS version. If there is, just click "install", and it will go through the motions.
Also unlike Windows, there is only one OS 'image'**, which works for all supported Macs. There are no additional driver packages or whatever that need updating and installing.
One other point: Macs don't really need any 'maintenance' to improve performance. And you don't need any utility apps that promise to maintain your Mac.
** Well, ok: if Apple releases a brand new model after an OS release, then it may need a special build that includes new drivers for that new hardware. However, the next general release of the OS will then have those drivers included.
