No.
Hoplites and Immortals used spears, Roman legionaries mainly used pila (which are heavy javelins, not spears, and it's even debatable whether they can be considered their primary weapon, since they were cast in a short-distance volley at the approaching enemy), what 'knights' (for lack of a better term) used when they were not using a lot of other war-implements were lances, and tercio soldiers (or more precisely, about two-thirds of them) used pikes. All of which are quite different beasts.
Yep! Different beasts which share the relevant unifying qualities listed, and which are usually classified under the spear taxonomy!
https://en.wikipedia.org/wiki/Javelin said:
A
javelin is a light
spear
https://en.wikipedia.org/wiki/Lance said:
The
lance is a
pole weapon or
spear
https://en.wikipedia.org/wiki/Pike_(weapon) said:
A
pike is a
pole weapon, a very long thrusting
spear
Or which might not be so classified. I'm not looking to pick a fight if you've got strong feelings about Spear Ontology!
I do agree that Roman legionaries are a questionable inclusion; most people would either say the gladius was theirs, or that they were a case of fighters who didn't have a primary weapon. (Since the gladius's effectiveness was reliant on some amount of the enemy line's shields being disabled due to having pila in them.) Feel free to discount them from the list of primary spear-users.
Well, I'm against lumping together these weapons (in this very case, not in general) simply because Battle Brothers differentiates quite sharply between spears, pikes, billhooks etc. (where's muh halberd?), so I feel we should do the same.
The point of discussion was whether a spear is, so to speak, more of a "noob" weapon than others. And a cavarly lance is definitely not a noob weapon (apart from aiming, it requires a lot of training to learn to extract it correctly from the enemy while the horse is galloping past, without having it breaking or being wrenched out of the hand). A pike requires a certain amount of training to syncronize with the others pikemen, avoiding clocking on the head your mates five rows in front of you, how and when to hold it properly in order to break arrows' flight, etc., plus it requires two hands to handle, so no shield (or only a small one hanging from the shoulder as in the case of Macedonian pezhetairoi), which poses an additional set of problems, and in general a pike unlike a spear is a bugger in close combat, which is another factor than does not make it a noob weapon. A pilum is more difficult to throw than a standard javelin, since it point of balance is further back along the shaft, and it needs to meet the enemy shield straight on in order for its really thin metal head to wound the enemy behind it, so definitely not a noob weapon. The Immortal spear was of a peculiar kind, with a metal sphere at the butt, which would make it quite unsuitable for throwing (and more difficult to use overarm), but would make the point more nimble and better for precision strikes, so again not a noob weapon.
Conversely, a spear in conjunction with a large shield does not require much training at all to use: keep your shield up, and poke the enemy while holding the spear overarm in order not to inconvenience your mates. Which leaves the Greek hoplites who, incidentally, were for the major part (excluding the Spartans or mercenaries) more or less noobs, certainly not elite troops in terms of training or battlefield experience, since many of them were simply middle or upper-middle class citizens who could afford the hoplitic panoply, and when it was time for war participated as hoplites, then went back to their business.
To wrap it up: the advantages of a spear are reach (compared to sidearms, not certainly to all weapons), cheapness and relative ease of use. It does not certainly have magical "armour piercing" capabilities (outside of movies or videogames), and a spear held two-handed does not "let you apply more force to your target" any more than a thrust for example from a two handed sword, just like a spear held in one hand does not "let you apply more force to your target" any more than a thrust from a pointy one hand weapon (weapon-weight and weight distribution aside).
In general, the fact that a weapon does not require much training to be used at a basic level does not make it any less effective, and saying that it is not so because it was used by elite troops does not make much sense: a flanged mace is definitely an easy weapon to use (bash your enemy with it, you don't even have to worry about edge-alignment as with an axe or face-alignment as with a warhammer), and yet it was used mainly by elite troops (mounted men-at-arms or knights in full armour) against other elite troops (other men-at-arms or knights in full armour).