But there are plenty of markets where Apple did fail miserably - enterprise/servers, TV, netbook competition (the air), to name a few.
Servers I grant you; that just isn't Apple's strong point. TV was always presented as a hobby, and is not a market where anybody has done remarkably well. I don't see how you can describe the Air as a failure. Just about their entire laptop lineup has some Air DNA nowadays, and they are still doing pretty well in a shrinking market. No, the Air was not a netbook killer, but Apple never pretended it was, and netbooks did not need a killer.
Apple's success rate is well below 50%, so betting against them is actually a pretty good bet, especially in the post Steve era where all innovation has been killed off by Mr Cook.
Measuring success rates is a bit more complicated than just counting the products that failed and succeeded. More telling is: what significant new product markets did Apple miss after the Jobs era? The best example I can come up with is drones, but that is already pretty remote from Apple's core business. Ebooks perhaps, but that's also not a strong example. Possibly the interactive stuff Microsoft is coming up with nowadays. Apart from that I can't think of anything really significant.
Therefore, to me AR is the first post-Jobs technology that Apple cannot afford to miss. At least they are working on it. Again, for technical reasons I have my doubts anyone can do this well, but since Apple seems to be determined to make a splash here, I am not betting against them.