If you believe that figure, that's still comparable to solar's best ( https://en.wikipedia.org/wiki/Solar-cell_efficiency ).
Optimal steam plants can get do better, exceeding 50% in some configurations ( https://en.wikipedia.org/wiki/Combined-cycle_power_plant#Eff... ). Steam is awesome.
The difference that makes your statement misleading is that solar doesn’t pay for its fuel, the sun shines for free.