CIV Total War

Yes, agreed. The comments are more general - for example by "swords" i refer to the generic melee infantry unit that in MTW/VI are swordsmen/axemen mainly (polearms to a lesser extent due to low morale and anti-cavalry bonuses).

In STW these are: Warrior Monks, Naginata and NoDachi.

In MTW the swords are overpowered for their price (in MP) and the spears underpowered for their price that in fact gave two only viable competitive armies in MP to my understanding: the all cavalry and the sword/cavalry army.

In the original STW the spears had good enough morale and could stand better in a melee with sword infantry so they did more part in MP gameplay as a clear component since swords generally fared badly against cavalry.

That approach was defining a more clear RPS (Rock - Paper - Scissors) gameplay that in MTW was lost, since as you say swords can withstand charges and subsequently beat cavalry in most cases, so they are way more effective and all purpose than the low morale spears since they have higher attack stats generally. Spears will pin for longer but also kill much slower.
In the campaign these relationships are further distorted by upgrdades: armour/ attack/ morale/ valour and the general's stars.

I've also read that in MTWv1.0, spears (100 man units) would beat swords (60man units) face to face and that this was changed in the first patch because people complained about it. Swords would still win by flanking though.

Swords withstanding charges and beating cavalry can change though if they have suffered heavy losses/got tired/got encircled or all three -charges can rout them then and this is very important in the "finishing" stages in an MP (and in SP but there you can have uber units by the upgrades) game that morale due to fatigue reigns supreme and units are scattered and undermaned throughout the map.

Many Thanks

Noir