The conclusion is spot-on. Business articles have been written about how Apple still acts like a startup in many ways. They run a tight ship, not wasting money on things like pure research (which Microsoft does a lot of).
It's goal is to maintain, and come out with slight improvements to each of its products
Slight? The iPhone 4 was a completely different piece of hardware than the iPhone 3GS, new case, new brains, new screen, etc. In general, companies with successful product lines do tend to upgrade them over the years. Even the current XBox hardware-wise is quite different than the original even though it has to keep the same performance specs (they actually introduced wait states in the latest SoC to mimic the FSB latency of the original).
Besides MS now being a competitor to Apple in the mobile arena
And you say pay attention to facts? They have been competitors since the iPhone came out against Windows Mobile, which had a US smartphone marketshare of 40+% at the time. You probably don't remember the two being in competition because the iPhone caused that marketshare to drop like a rock, down to 15% within two years. Then the combined iPhone and Android pushed it into the realm of "Other" in three more years. Microsoft tried to come back with Windows 7 and the Kin, and failed miserably, even with the help of Nokia.
Apple is tiny in the OS arena, and in gaming, and in search engines (Apple has none), Office software (MS is thinking of writing (or releasing) Office for the iPad), in server software, in the browser market, in web presence, where MS has a huge web site, and one of the biggest e-mail applications in the world, if not the biggest, and Skype and, in reality, hundreds of other applications for development and productivity.
So, Microsoft is diversified into multiple areas, most of which don't make much money. Good for them, big tail to support with little return. They're branching out into more areas where they have no idea how to make a profit. And that's what this is about, profit, return on investment, not a big checklist of things you're involved with.
Microsoft has bought many companies with no apparent return, over a hundred total in the last 20 years. Buying for the sake of buying mostly, diversification for the sake of diversification? And where has that gotten them? A flat stock price, relatively mediocre profit margins. WebTV was an attempt at diversification, almost half a billion dollars wasted, and Danger made a billion wasted. Others were smart and strengthened product lines, like buying Bungie and Rare to ensure top titles for the XBox. This is the kind of thing Apple would do, making sure product lines are strong and not vulnerable to outside influences.
Meanwhile, Apple has bought 30. Let's see some I remember: Bought out Next, the source of the wildly successful OS X that has seen millions of people switch from Windows to it, and really they bought Steve Jobs who made them the most profitable company in the world. They had to buy out Power Computing to end the clones (a brilliant move that brought Apple back from the dead). They bought some semiconductor businesses and a stake in others, which has turned a huge profit in the iDevices. They bought lots of software companies whose products fed directly into profitable Apple software like Final Cut Pro, iTunes and iOS. And of course those mapping companies bought to break free of Google's service. And Apple's going down-chain too, buying a flash memory company. You probably didn't know it, but one of the secrets to Apple's success is extremely tight control of the supply chain.
Apple still has the 3 "sub-products", with supporting software. Other than that, they're ridiculously outranked when it comes to the number of products and services.
Those are simply markets that Apple does not choose to play in. Just because others have, doesn't mean Apple has to. For example, Apple doesn't play in the low-profit area of sub-$500 computers, and that's a good thing. Should Apple duplicate the money-losing Bing search engine? I remember not long ago Bing was losing a BILLION dollars a QUARTER. Apple doesn't like to lose money, even as a loss-leader. Apple likes to make products that turn a profit from day one.
If they don't wish to spend on R&D, then they better hurry up and purchase some other companies which will make them more diversified.
They're already spending billions on R&D. It is obviously enough to ensure current products don't become stale (Mac Pro excepted), and to ensure new products can be produced.
As far as buying companies, sure, maybe Apple should buy Pepsi. They can afford it. Doesn't mean it is a good fit with Apple's current business and culture, but hey, it's diversification for the sake of diversification. But as noted above, Apple has been strategically buying companies, over $800 million in chip companies in the last few years alone. Apple also has a big stake in Imagination Technologies, the leading designer of graphics chips for mobiles, and spent at least $400 million on mapping.
Remember this discussion, because, in a year or two, Apple won't be flying so high, and they could turn out to be the next Palm or RIM.
Apple destroyed Palm and RIM by doing exactly what they're doing now. Apple mostly destroyed the netbook market with the iPad. And you want them to change this winning strategy to fulfill an MBA buzzword?
It is two different philosophies: Play in everything and see what sticks, what turns a profit or not. Or, create a small range of highly-developed, highly-targeted products that will turn a profit. Obviously, the former has not served Microsoft's stock well over the last decade or so. Obviously, the latter has served Apple very well.
You have yet to give any evidence or make any reasonable argument as to why Apple's winning strategy should suddenly cease to work.