Ok, look at it like this. I can build a Paladin to use Strength or Dexterity. What does this actually mean?
-Strength Paladin can use heavy weapons. Strength Paladin can, after spending a lot of money, get a little more AC. Strength Paladin can lug around more gear, and is better at Strength saves (which generally only apply to effects that push you around or knock you prone). Strength Paladin is good at Strength skills.
-Dexterity Paladin has to use weapons with the finesse quality. They are better at using ranged weapons. Dexterity Paladin has to spend a lot less money on armor. Dexterity Paladin is better at Dexterity saves (which generally apply to effects that cause hit point damage or hinder movement in some way). Dexterity Paladin is good at Dexterity skills. Dexterity Paladin has better initiative. Dexterity Paladin is far better at Stealth.
The takeaway here is that the main advantage of Strength Paladin is more damage and being good at Strength skills. Strength saves don't come up often and the penalty for failing them is far less of an issue with other saves.
Dexterity Paladin is more versatile, being good with ranged weapons. They have better initiative (which you may find valuable), Dexterity saves are much more common than Strength saves, and taking less damage is always nice. Dexterity Skills vs. Strength skills is a preference, I find they are both nice. Dexterity Paladin doesn't have to wait as long to get their best armor. Dexterity Paladin is better at Stealth.
There are tradeoffs to both approaches, but Dexterity Paladin gets a bit more upside, if those things are important to you. Hence, one can say Dexterity seems like a better attribute to have than Strength.
But on the other hand, if you want more damage per hit, and you plan on using Great Weapon Master, the advantages of Dexterity over Strength are irrelevant. You can't make that choice, so even if Dexterity is the better attribute on paper, it makes no difference.