Again, this comes from the idea that they need to make their profits look better and better because their stockholders demand it, which is sometimes at odds with what the players are looking for.
Do you think Maxis failed on its own, or is there the possibility that EA milked it dry and left it to die? If the latter, why would they do that? Not because it's good for the company long-term, but because it makes their bottom line look good just before annual profit reports are coming out. Think about it: SimCity was rushed out to meet a deadline of the end of EA's fiscal year, which happens on March 31st. SimCity was released March 7th, 2013. What's today's date?
As far as the stockholders go, I can assure you that A) stock holders have no ability to influence the release schedule of a video game or B) care how profits are generated, only that they are. There is at least a passing argument that the massively successful franchise of the studio would not have been possible without those stockholders, and the studio certainly did not turn down the money when they were acquired.
Whether EA mismanaged Maxis specifically or their management is in general too fixated on short term profits is not the issue. "Wall Street", whatever that is, does not demand that and would more happily not be involved in those decisions. So is it possible that EA is mismanaging their studios in a misguided attempt to cook their books? Maybe, but if so that has been true for Maxis for going on 2 decades, 1 of which was hugely successful.
You can blame "Wall Street" all you want, but it seems a simpler explanation that in a blockbuster driven market, Maxis failed to deliver blockbusters. This isn't surprising in the least given most software projects fail and even more so with games. I find it surprising that Maxis lasted as long as it did quite frankly. An independent studio would probably not have survived Spore, and I think Maxis did largely because they were backed by "Wall Street".
If you still don't think Wall Street has even an indirect say in what games get published when and at what quality, then I don't see a point in continuing this discussion. But I'll leave on the point of SpaceX not wanting to go public until they make it to Mars, because Elon doesn't believe that stockholders will let him take the risk of sending humans to another planet. Or, taking a step back from Wall Street and just talking investors, the idea from this very community that any exit for a startup is good and is favorable for your investors even if it leaves your customers high and dry. Or how about when Steve Jobs was pushed out of Apple because he wasn't making enough money? Apple raced to the bottom and lost, hard, in the pursuit of maximizing profit.
I'm not trashing the idea of Wall Street or of investors. This is EA's fault. But saying that investors don't influence a company's products is insane. Of course they do, to the fullest extent that the company will let them. Again, if you don't believe EA is completely controlled by their investors, take a look at the timing of the end of their fiscal year, the rushed release of SimCity, and the announcement of Maxis being shut down. That's not coincidence.
Wall Street, even as the completely generalized abstraction, doesn't have anything to do with this, other than a big video game publisher used some money generated there, to back a studio that has been unsuccessful at their job. If it had been a US governmental bailout or kickstarter that the financing came from, would not have changed that.