But also? Nobility would not be part of the spearwall. Or, to be more precise, they would not be part of the first spearwall and may only be part of a formation that comes in to mop up when the battle is all but won. Or they would be mounted tanks in the form of plate armor (more richard than alexander). They key being that they would be able to get their blade wet but would be in little to no danger.
I loathe to compare the two as I think Zelenskyy is actually a genuinely good leader who is focusing on his role as a political leader, but he is actually a really good example of this. When things are comparatively safe he’ll walk the front(-ish) lines and get face time with the soldiers to maintain morale and get photo ops. But mostly he is a politician in camo pants who is making sure that the people who actually are fighting for Ukraine’s survival have guns and ammo. A more “strongman” style leader might argue that as being “he is on the frontlines fighting alongside the heroic men and women of our army” but he is never in any meaningful danger.