The Start Menu is a great search and browsing tool. I myself use Start8. But it's hardly enough to deter for the desktop environment as a computing environment. The improvements over Windows 7 are vast.
Obviously because I do use Start8, I realize how important of a search tool and browsing tool that is. You don't use the Start Menu that much, but when you do, Modern UI Search is unacceptable to me. If that was truly unified and you could drag to select a whole range of results and perform in-place context menu options, I would not mind it myself.
I do think the Start Menu should/could be a feature advanced users could add. I have not problem with it being removed by default. I actually have no problem with the Desktop Environment being an advanced add-on feature. Of course, top notch Modern UI core apps would be required for that, which doesn't appear to be happening even after the fact.
Again, someone at MS incorrectly believes desktop computing is diminishing or losing significance. They are just ... wrong. That fallacy is why things seem so messed up to so many. Not only are they wrong, but their consumer tablet initiative which they seem to have sacrificed much of the hardcore desktop computing users for, is a total failure (my opinion, and I own a Surface.) The Surface Pro is NOT a consumer tablet at $800 and is instead a laptop/ultrabook alternative. It's a full blown PC.
Other than my own workplace, I have not seen a single person with a Surface RT but have seen tons of new iPads and Android tablets which are multiplying like roaches.
And that is *entirely* due to price (Android tablets) and the overwhelming number of apps (iPad).
Android is flourishing entirely based on price. Never mind that the low-end tablets are, in fact, mostly forks from the defined standard - they are cheaper than Surface, and that is, in fact, draw a-plenty. (Basically, it's the same impact the Gang of Nine had on the IBM-compatible market.)
However, if you need a large app variety, Android isn't it, and even Windows+RT isn't it - iPad is.
Start8 offers a large number of features the original Start Menu itself lacked - which is part of its draw. The other reason Start8 is popular is, in fact, that it uses the familiar UI - there's nothing new to learn. (It's improved old, which will outdraw new almost every time - and especially now, when improved old is itself a major draw.)
I have nothing against Start8, other similar utilities, and certainly not against Stardock - I use quite a few of their utilities myself - just not that one. (I have Decor8 and DeskScapes 8 installed right now.) However, Start8 is what it is - a Start menu with improvements the original version lacked - it's NOT identical. If you want something utterly identical to the old SM, then you want Classic Shell - not Start8. Comparing Start8 to the Windows 7 Start menu is not fair to either.