Yes, I and every other person reading this know what he is responding to. The point is that he bought the laptop and wants to immediately use Linux. The advice given, and what is being responded to, is to image the drive with the clean installation of Windows that is currently on it so that you can revert back to it as though it were a factory install if the OP decides to sell the laptop later.

fresh install of Windows will always be superior to a re-image of an install that's been on it for a long time

The problem, which I was pointing out and you fail to have seen as well, is that the image would be of a clean installation of Windows, and not a bloated, slowed-down instance.

Therefore, the argument is essentially about whether an image of a clean install or an actual reinstallation is better. I would like to note that one argument was that the OP will have the auth key for the copy of Windows, which isn't necessarily true. Windows 7 PCs had a sticker containing the auth key, but Windows 8 PCs do not. I am not sure if Windows 10 does, but that may preclude a person from easily reinstalling windows.

Furthermore, a fresh installation of an operating system will not include the Dell specific software that is included with Dell reinstallation disks. Therefore, the OP would have to procure those disks, which usually comes with a base fee and shipping, if he wishes to return the laptop to factory settings later.

The advice was a simple workaround for saving a copy of the laptop exactly as it came from the factory so that he can later sell it as though it is brand new (with the exception of physical wear).

Is a factory installation preferable? Of course. Which is easier to achieve with the least money spent? Not buying factory installation disks.