Tldr
A cover is not normally required for hiring in most kinds of occupations, except to explain an unsolicited approach.
OP's example
I have to admit I find the example given quite bad. It is worded with fluff, it has a tone of considerable informality, and for anyone reading it it is probably a complete waste of time compared to if they had just proceeded to read the CV.
So I would suggest that providing no cover letter would be a better option than providing anything like the example, unless it's the job to be informal and talk empty fluff (to your own would-be employer, I mean).
The past
The notion of a cover letter is really a vestige of the hiring practices of large corporations decades ago.
You couldn't just send a CV to a central hiring manager or personnel department, and expect them to know what your CV related to. You had to explain what position you were applying for. The letter might not even be opened by the principal in the first place.
And it also wasn't easy to retailor CVs. People often had several copies typed up at once on a typewriter - changes required access to machinery, a replanning and resetting of layout, and time and concentration to re-enter a few pages of text accurately.
The cover letter allowed people to scribble the introductory information, provide a few relevant bullet points which may not have been in the CV itself, and articulate other niceties in an era when written communication was regarded as more formal.
It's also worth nothing that back then there were alternative practices in smaller businesses, or in occupations where this level of sophistication couldn't be expected. Usually, a chat with the candidate, and then a chat with his current/most recent boss.
A short written application letter - as the primary document, not covering a separate CV - might have been expected for some routine positions where clerical competence was expected. The quality of handwriting would probably have counted for as much as the content.
Today
Nowadays, job boards organise the introductory information that would have been in a cover letter - there is no need to include a cover letter on top when applying by these means.
And computerised CVs are easily modified - employers generally expect the CV to be produced so as to be sufficiently relevant and appropriate, not for candidates to act as if their CVs are fixed documents, which they then supplement with yet another document.
When a cover is required
The only time a decent cover would be required, would be if you were making a completely unsolicited approach by email, where it can't be assumed there is a process in place to gather CVs for later review, or for the recipient to even understand why you've contacted them.
Here, an immediate explanation of your motive is required, and niceties required to urge the recipient to read or retain your CV, which they weren't expecting to have to handle.