I largely agree with the sentiment of the article, however I'll play devils advocate here and start by saying that digital has made monster strides and improvements since the first commercially available cameras hit the market just over 12 years ago, so upgrades have made sense for those shooters good enough to push their gear to the limits. Physics tells us however that we have pretty much reached the pinnacle of what's possible with digital and only really have incremental improvements to look forward to, at least with respects to IQ. Features are another thing though,...cough video. Secondly the idea that digital upgrades are cost prohibitive is debatable. I take my own gear use as an example. I purchased my D700 in 2009 for around $2700 and recently sold it for $1650 so that means it cost me $1050 for over 3 1/2 years of use, or about $300 a year, and on that camera I took tens of thousands of pictures. Work that out to a cost per picture figure and I'll take it, heck anyone running a business would say that kind of overhead is nothing. In the days of old photographers may have settled on a system and nursed it for a decade, but they also spent mountains of money on film, and if they wanted the good stuff, they spent even more.
Again however, I will say that I do largely agree with the article, most shooters don't come close to maximizing their gears potential, and I include myself in that sentiment. However for me, to use the best gear that's available removes any and all excuse that I could come up with for not taking good pictures and in doing so this allows me to focus solely on shooting. Perhaps it's mental,..in fact I know it is, but for $300 a year, I'll manage it.
Long live gear lust, lol.