Uuuh Holdo’s plan is not to make a last stand on Crait, they were supposed to hide there unnoticed because of the cloaked (I believe) transports, while Hux is busy destroying their capital ships. This is foiled because of Poe’s plan going wrong (DJ overhearing about the cloaked ships). Also, in the nicest way possible, I don’t get the obsession with human sacrifices, especially those of younger characters. In the movie, Holdo realises that their best sure shot for survival, considering they can’t just jump to lightspeed, is to let the FO destroy the ships while saving almost all the people. Poe and gang come up with an all or nothing plan with too many points where everything can go terribly wrong, which we see unfold and ultimately screw up the Resistance command plan

edit: I’m all for thought experiments though!