[katmannthree]

> trying to keep warm, gaseous hydrogen under high pressure

Which of course nobody would do? Unfortunately, those are the circumstances in which H2 is made from fossil fuels and likewise the circumstances under which it is combusted in turbines. You can't just handwave materials compatibility away.

[ncmncm]

Keyword is "keep". Hydrogen will not be penetrating and weakening turbine blades.

[katmannthree]

The turbine blades are downstream of the combustion chamber so they handle combustion products not hydrogen-rich gas. The turbine combustion chambers, fuel handling system, and high pressure H2 compressors[0] _do_ have to function in a high pressure high temperature H2-rich environment.

0: Take a guess as to what those look like inside.