It is the Latin language that takes a real beating here; misuse of terms is rampant:
* Pila and Pilum are talked about as two separate things. They are not: pila is simply the plural of pilum.
* There is no such thing as a gladius hispanicus; the correct term is gladius hispaniensis.
* There is no such thing as a loricum; perhaps the author was thinking the feminine lorica was instead plural, and so attempted to make it singular and neuter, but this is incorrect.
It seems odd to leave the Carthaginians out of the story as the Romans' initial inability to overcome these foes, and the subsequent adoption of many Carthaginian tactics, equipment, etc. was what the Marian reforms were all about. Additionally the Romans initially encountered the Celtiberians as members of the Carthaginian forces, which is how they adopted the gladius hispaniensis--which some would say is the original incarnation of the gladius with exclusively xiphos-like swords being used to that point---and arguably the falcata (and here it is probably also worth noting that this word is a Latin neologism for this sword, meaning something like "sickled").
Lastly, it feels a bit incomplete to not bookend this tale of the rise and spread of the gladius with a discussion of how it was eventually eclipsed by the spatha.