Many people would have preferred Ackbar take command and do the "lightspeed suicide run" instead of Holdo (Laura Dern's character) but it causes some problems with the story (as presented)
If Poe mutinied against a character we've loved since 1983 (either Ackbar or Leia) audiences would have been upset and hated him for it.
Therefore, if the plot requires him to mutiny against a plan he considers bad, they have to bring in a new character (Holdo) that we are LESS vested in (than him) in order for the audience to accept his decision to mutiny.
Problem is, in ANY OTHER MOVIE PRESENTING THIS SCENARIO, the Holdo character would have ended up being either 1) a spy or 2) incompetent. But TLJ is all about "subverting expectations!" so neither happens, making everyone's decisions seem pointless and unsatisfying.
Poe (and to a lesser extent Finn and Rose) are responsible for all the extra needless deaths, yet Holdo is the one who sacrifices herself. And then Finn tries to sacrifice himself but Rose stops him. It just doesn't make sense from a character arc standpoint.
None of the new Star Wars movies make any sense from a character standpoint. Consider this: Who would be more broken up over the death of Han Solo - Rey or Chewey? And yet, at the end of Force Awakens, Leia walks RIGHT PAST CHEWEY and instead hugs a woman she's NEVER MET BEFORE!!!