It’s because of how accounting works (opex vs capex). I don’t know if there are tax reasons but a major reason opex is preferred to capex is that the former is tied directly to cash flows. Cash flows are the lifeblood of a business being profitable and makes it easy to balance costs and revenues whereas capex is a long term investment (ties up your capital).

There are secondary order effects going on here to explain this. Also, in your example the 50k number isn’t including the rack space rental costs, technicians to maintain the hardware, and OPs people to keep the deployed software running (software updates etc).