I can't believe this article was written by the EDITOR IN CHIEF! Not only are the suggestions unnecessary for intermediate and advanced users (they are likely to know them all), they can be downright dangerous for novice users.
It's NEVER a good idea for novice users to unhide system files and extensions (and your comment about not knowing if it's a XLS or XLSX is fluff, as Office handles both just fine, and there may be a specific reason it needs to be in the older format), nor delete the system restore partition.
And how is "Setup OneDrive" not on this list? For novice users the free allotment of space is a great way for them to help protect their documents and pictures, especially if they have to do a system reset, without having to remember to do backups. Heck, "Check for Windows Updates" isn't even on the list, but "Update Your Graphics Driver" is?