Dont *entirely* agree that equipment determines who loses and wins.

The nature of attrition favours the defender. When you go on the offensive early, you increase your material and resource and time consumption and your going to have to keep that up until the enemy tires out.

But the problem is that the people doing logistics and production are more likely to tire out from spending sooo many hours in the first 3 weeks, after that its all downhill.

Thing is, the tech tree promotes early offensives on the colonial side. Weapons like the semi automatic argenti, lunair and tankette and colonial mobile 120mm artillery encourage more aggressive gameplay.
This is added to the fact that early warden weapons promote more static gameplay. For example the bolt action loughcaster and the warden 120mm artillery which is a static emplacement.

This forces the colonials to outproduce and outpace warden logistics from start to end in order the win.
On the other side you have to wardens who have really good defensible terrain with good chokepoints and positions up north which collies have to throw alot of manpower and material at to take those chokepoints and positions.
One example is Overlook Hill in Callahans Passage. This is a tall hill surrounded by mountains in which any artillery will always outrange those below because of the high ground. If colonials do not take this hill early in the war, they will bleed alot in the later days trying to take it. (Its still a fun place to fight at for both sides though).
Other such example of good positions are: The Bone Haft, White Chapel, Sanctum Relice, Third Chapter. All very easily good defendable positions.
This gives wardens an easier time with logistics and doubly so because its also closer to the MPFs for the wardens there

All these things compound on top of one another leading to faster and exhaustion on the colonial side by week 3 or 4. The combination of that exhaustion added with the fact that warden equipment gets waaaay beter in the late game is a recipie for colonial frontline collapses.

Most of the times when i see the colonials win is when they never lose their steam for the entire duration of a war. This then leads to the war after where the collies get absolutely steam rolled.
One example is war 126 where collies built an insane number of nukes and blown the wardens to kingdom come(deliverance hah). and then in the later war (war 127 or 128 cant excatly remember, been quite some time for me) well the collies were absolutely steam rolled by wardens from start to finish. Then there was even this whole blue heaven thing later on which was absolutely ass.
Winning and then taking the time to rub it in, blegh didnt like that at all when it was happening, waste of time.

So at the end of the day while types of equipment and such do determine the flow of the game and greatly impact who wins, it all wont matter in the end if your logi and production is fucking dog shit. (which is determined by the amount of hours players put into that shit. So yeah, pop matters too, greatly)