Just art, or a peak into the future?

[Endemerrin]

one reason to not give them to gladiators would be that gladiators already also get daggers, though I'm not terribly well informed about how different they are from regular swords

I'd imagine it'd more likely be a marauder weapon honestly.

Daggers are just high accuracy/low damage one-handed weapons. Not really any major difference from other gladiator arms - just tailored to a specific use, like the rest of the variations of one-handed blades. However, they lack a weapon with any umhpf - which is exactly what a two-handed weapon could bring to the table.

Marauder already has a two-handed weapon. I'd almost figure we'd see one-handed axes for Marauder before an entirely different type of weapon.