That's not an accurate summary, or at least it's not complete. I took the author's main points to be that (a) 37Signals's offerings are viewed by customers as investment opportunities instead of as consumable goods, and that (b) people are thus more willing to pay for 37Signals's stuff than for the mere "consumption-services" offered elsewhere. The author implies that this is the case even if those consumption-services provide a lot of utility.
Point being that in the author's mind, it's not that 37Signals is making great products while everyone else isn't. It's that 37Signals is making great products that are seen as productivity tools and hence as investments, rather than as simple absolute costs.