The “razor and blades” pricing is (as the market demonstrates) a dominant strategy. The other pricing strategy (cost-plus) is preferable for the customers printing a lot, not for customers who print little. Then add some customer myopia: I need a cheap printer, where cheap is initial out of pocket, not total cost of ownership. And there you have it: all suppliers ‘must’ follow the dominant pricing strategy because the myopic customer demands it. The twice as expensive printer up front just won’t get store space.
Brother might be (or, was?) somewhat of an outlier for the informed consumer. But who buys a Brother right? HP and Canon dominate the market.
General point is that individual suppliers in a multi supplier market have to take the dominant pricing strategy as a given, or differentiate along other axis.