Like most things, different companies bring different things to the high end market. Companies bring different things to the high end bike market. So you can choose from lightest, best race team, flashiest, most durable, best service, best suspension, best design, etc. If you are lucky sometimes more than one. I recommend you take a trip to the most serious trail near you. I think you'll find the popularity of bikes that you actually see on the trail is unrelated to marketing, unrelated to what you see in the bike magazines, and unrelated to what you'd guess by visiting bike stores.
If at all possible I'd look at a more famous place like the popular trails around Tahoe, Downievilla, Moab, North Shore, etc.
For my last bike my wish list was: lifetime frame warranty, threaded (not pressed) bottom bracket, and boost. Other than that I just wanted the one that felt the best. Took me 3 demos of 2 hours each to finally decide.
If you are looking for most reliable I'd check the rentals. If the bike survives a season of rentals without a prohibitive amount of expensive maintenance and parts it will likely last you a life time.
I can assure you that fox forks can last over 5 years without maintenance, but the recommended maintenance schedule is somewhere around annual or 100 to 1000 hours of riding or so.
Current high end disc brakes from SRAM or Shimano can be squeal free under most conditions, which is one of the reasons a large fraction of the high end bikes have switched to them.