If they aren't making a profit they aren't creating value. They are destroying some value and transferring other value from investors to customers. The difference here is when you add everything up you have less, when for a good investment the total should go up.

In principle, in a fair market economy, that is OK because someone has to take the risk of being wrong about what is a good idea.

The concern being voiced is that monetary policy is diverting resources away from people who are known to make good long term decisions and towards people who have access to loans from the central bank. At some point the people who are borrowing money can't pay it back and the losses are revealed - not in and of itself a problem; those responsible take the hit. But in the mean time, the people who would have used the resources more sensibly to build infrastructure or sustainable logistics chains havn't been because they weren't being given the time of day by the markets.

The worry is that a dropping tide lowers all ships. If value is being systematically destroyed and the cause is government incentives then the potential for that to crop up in unexpected places is quite high. I'm always tempted to link monetary policy to the themes of pension issues, low real wage growth, poor infrastructure and rising inequality seen in the US.