Microsoft will never be irrelevant... nor will it go broke/out of business because Win 8 didn't charm as many users as they'd have liked.
Funny thing, I heard the same/similar questions being asked around the same period after Vista was released.... all the haters jumping up and down and saying it was the demise of MS. Then Win 7 came out and it was the bees knees of all OSes... better than sliced bread. Well I used both Vista and Win 7 in 64 bit, and frankly, there was little difference between them, just a tweak or two here and there, but still essentially the same OS underneath.
Hmmm, the human race, such a fickle bunch and so hard to please... and let's not introduce anything different... cos they're so afraid of change and fech that, resent having to use their grey matter to learn something new/different. No wonder witches were burnt at the stake... they dared to show humanity there were new and better ways to do things.... and then humanity showed its inhumanity and murdered them for thinking outside the square/accepted norns.
To be honest, I am surprised mankind has progressed thus far, given its propensity to shoot new and innovative things down in flames.... and here we go again, another 'let's burn Microsoft at the stake' thread for the haters to jump on board... that is until Windows 9 hits the shelves and it becomes the "must have" OS of all time, beating even Windows 7 for popularity and sales, yet it is just a refined version of Windows 8 with a few extra bells and whistles... yet at core level, exactly the same underneath.
So what do I find irrelevant? To a large extent, the human race... because it is too full of its own self importance and has little time to consider anything he/she does not consider directly beneficial to him or her. So when I think of Microsoft, I think of Bill Gates and the great contribution he has given the world, not only as a tech entreprenuer, but also as a humanitarian and philanthropist who thought outside the square rather than bitch about change.
Both he and Hugh Hefner would have been burned at the stake if it hadn't been outlawed in 16th century Salem, yet these two men have done more for civil liberties and human advancement than any other two men on the planet. So is Microsoft irrelevant? Only if Playboy magazine and titty girls are as well..
Oh, and irrevellent is when a vicar has been defrocked for reading Playboy in the chloisters on God's time.