Nobody can decide whether an all-new tech is mature or not without fully testing it. For the new DC-based IEP, you can't 二even find a single surface combatant in any part of the world. According to your logic, PLAN will never try it since it'll never turn mature.
No. According to your logic, the Tianwen Mars mission would have to take a relatively unknown and untested engine on its very first flight and cross your fingers, if anything else fails, we will improve it and try it again. That's nonsense. Everything is thoroughly tested on the ground, and even on the ground you can replicate the conditions where those systems are expected to confront.
This is why an industry creates a tight set of formal standards and the system has to pass through a long series of static tests. Its not as if you cannot create static tests for engines on the ground that can simulate its operating conditions. Before the engine ever gets into a ship, the engine has to pass through these series of testing. So before the engine ever gets to the 054B, it will be thoroughly tested through all these carefully engineered tests, standards and qualifications, and every box has to be check marked before the brass approves the final checkmark.
Kind of boggles me that you would think the PLAN and CSSC would go half assed on this.