Microsoft is not in the console gaming business to make money. They are in the console gaming business to bring competition to Sony. No matter how much money they lose, or time they invest, they will not leave the console gaming business until either Microsoft dies, or Sony stops making the Playstation(unless investors demand it, but they never have and they very likely never will, especially when Obama keeps bringing up their brand in every other speech). F'n with the Playstation is the current goal(see competition disruption), and the Xbox is the monkey wrench for their plans.
You see, a few years ago, when the Playstation was released, MS was already in the gaming business on its Windows platform. However, Playstation and Nintendo were mounting serious competition to Microsoft in this respect. So, they cooked up the Xbox brand to disrupt the console gaming market, so they could gobble up a larger piece of the gaming pie, and bring down their competitors as MS is prone to do.
It's actually worked, if you look at their second generation console. It's actually outsold the Playstation console at this point, by a significant margin, and if it does "lose" this generation, it will likely be long after their next Xbox is on the market, and then only by a slim margin.
As for your question of "what if the PS4 is as popular as the PS2 again" that's impossible. The days of console dominance of that scale are gone. The fanboys have seen to that. There will never be a dominant console again, amongst core gamers. We are split. The PS2 came along at a perfect time. After a great previous generation, at a good price, containing new and accepted tech, DVD, with good launch titles, and most importantly, terrible competition. The Gamecube had a huge kiddy stigma at that point and time, and the Xbox was too expensive, and had a "doomed to failure, don't invest your money in this thing" stigma going for it as well, along with a lackluster lineup. The only choice for gamers really was the PS2.
No console shall ever again have an equivelant exclusive lineup, because everything is moving multiplatform. The advantages the PS2 had, simply cannot be had in today's gaming environment without casual support at a significant percentage. You might see a console do better than another one, but you won't see a dominant one at the level of the PS2 vs competition(again, I mean "without significant casual support" here). It's an impossible dream, especially with the brand recognition and prestige the Xbox has garnered in North America, gamings most influential region(imo).
...so no, no they won't. In fact, I think out of the big 3, Xbox is the second most secure brand.
I don't need your console war.
It feeds the rich while it buries the poor.
You're power hungry, spinnin' stories, and bein' graphics whores.
I don't need your console war.
NO NO, NO NO NO.
