Former Army Officer here (retiring rank of Captain) and I can say that there certainly isn’t an attitude that enlisted men and women are “expendable” or that officers are on a pedestal.
There is however a recognition of facts. An officer’s life is more important in the heat of battle than the lives of enlisted men. A good officer would recognize that keeping HIMSELF alive is the best chance for all of his men to perform well and get out of combat alive. You’re the one trained to lead, although NCOs are also very valuable in combat situations.
In Vietnam IIRC 2nd Lieutenants actually had the highest casualty rate of any rank.
Modern figures I have no idea, but remember there are going to be a lot less officers killed overall because there are a lot less officers in the Army.