subsidies are a red herring. the market isn't fair, and new technologies, particularly those like power generation that are inherently dependent on expanding or new infrastructure, cannot always stand by themselves because the already entrenched systems benefit from systemic bias cause by their mere older existence.
ie, the existing infrastructure is already there, already entrenched.
the new tech needs to build out new infrastructure.
subsidies thus serve two purposes: 1) help to overcome the inherent economic inertial bias of the current systems, and 2) to encourage the switch to newer more desirable tech that in the long run would be more beneficial.
coal, gas, etc, all already receive tremendous amounts in subsidies and systemic market advantages that are often overlooked or ignored.