The government subsidy is a point of criticism for "free-market" proponents. It's fair to point out that fossil fuels, and especially coal, have long benefitted from being able to externalize pollution costs. This is not consistent with an efficient market, since the extra costs of coal are borne by everyone regardless of whether they benefit.

Society has subsidized coal by both paying for negative externalities and through direct government investment, which is true for all waste producing energy sources.

This is orthogonal to OPs claim that "we subsidized solar until it was profitable is not accurate"