It's an interesting assessment and the brutally honest may have to admit that at the very highest levels of mountaineering there are egos at work; a degree of ego is essential at the top levels of any sport. That, however, is an entirely different from claiming that anyone climbing any mountain is only doing it for self-affirmation and that the only one interested will be themselves. The argument put forward is flawed from the moment it applies the answer to a question specific to the highest, and at that time unclimbed, point on the planet to every other mountain on the face of the Earth. "Because it's there" was specific to Mount Everest and because it was there, unclimbed, it represented more than the same question about, say, Mount Kinabalu.
The idea that 50 years ago only prosperous misanthropes were mountaineering is perhaps a hundred years out but the concept of being so dubbed would no doubt amuse the spirit of Don Whillans. The age of the prosperous mountaineer passed with the passing of the Golden Age of the late 19th century and 50 years ago a vehicle that may make it to the Alps and back was classed as prosperous. As for the "hundreds of thousands of people willing to spend considerable sums" considerable is relative and in reality travel is far more affordable to far more people now and the "hundreds of thousands" is again projecting the highest mountain in the world onto all other treks and mountains. The suggestion that "because it's there" applies to every mountain and every trekking destination is one of Saunders' own making.
In the same way that Saunders projects Everest onto every mountain he projects the menatality of society and state onto climbers. Pontificating about those he doesn't know doing something he has no experience of he seems unable to differentiate the desires of the climbers and the desires of the state both during the 1920s of Mallory and Irvine and the 1953 ascent. Yes, the machinery of state wanted to use the "conquest of Everest" as a political symbol of Empire but the climbers? I suspect the climbers' motivations were less of Empire and more of "climbing". The reasons why people climb are as many as the people climbing, and it's why Saunders will never get the definitive answer he seems to feel he's entitled to.
Pretending or not, the Himalayan climbing of the 1920's was exploration, both in geographical and physiological terms. It expanded humanities knowledge of our species capabilities and our geography of the planet. Despite the protestations of lacking "the purpose to be meaningful science" Mount Everest, in particular, has been a unique laboratory with valuable contributions to science for 100 years. Observations of how people survive at altitude with extreme low oxygen levels has helped in the treatment of acute trauma patients and physical observations help us in understanding the impacts of climate change. These, however, are the minority of mountaineers, for the majority the reasons and usually far more personal and individual.
Expanding from Mount Everest to include Mount Kinabalu and the other trekking and mountaineering destinations required to account for the "hundreds of thousands" decried in Saunders article I doubt you would find more than a handful whose honest answer would be "because it's there". Undoubtedly there will be a proportion who do it for self-affirmation, but is that a bad thing? Self-affirmation is said to help individuals cope with threat or stress and may be beneficial for improving academic performance, health, and reducing defensiveness; traits society has been trying to foster in our young people. There will also be many climb to escape the daily rat race just as the many who line the beaches of the Mediterranean. There will be those who trek or climb to push themselves physically and mentally and those who go to experience a different culture. There will be those who do it to learn about themselves and those who do it to learn about others. There will be those who do it because living in a land where we've become so detatched from nature it's a spiritual neccessity to be that close to it. There will those who do it for the exercise, and those who do it as the culmination of years of sacrifice and training. The times may have changed since John Muir said "Everybody needs beauty as well as bread, places to play in and pray in, where nature may heal and give strength to body and soul." but the human soul hasn't and in each of us there's an innate need that only remains in our mountains.
In stating that Mount Kinabalu is "very much entry-level egotism" there is at least a degree of recognition that trekking and mountaineering are different. Trekking is a business and an industry and it's the business that's responsible for many of the worst offences laid at the door of "mountaineers", with term being applied as a catch-all. Does climbing a mountain make someone a mountaineer any more than a photographer is just a person with a camera? There are questions to be asked of trekkers and mountaineers but they're questions that need addressing to the industries supporting them and the governments dependent on the dollars they bring. More emphasis needs to be put on educating tourists of local laws and customs during and following booking but at the same time. What happened with the arrested tourists on Kinabalu was something you'll see 100 times a night on the beaches of the Med, it's not the mountain that caused it or a deliberate act of law-breaking it was ignorance and a symbol of where western society is.
Me? I climbed because it was a way of escaping. Oh and far from nobody but a mountaineer being interested in what they've done the market for mountain literature and film has never been greater than it is today.