This is kinda a complicated question, but do you think any color has more exclusive effects than others? Like white is really good at exiling things, but for 7 mana colorless can exile anything like scour from existence or 5 mana introduction to annihilation. More so, I was looking at weird counterspells and I don’t think colorless can just full counter a spell for any mana value, all of them have riders.So is blue any more “exclusive” in its effect? Or does any other color have more things that other colors just can’t replicate

There are small number of effects, like counterspells, that we mostly keep out of colorless effects. It’s based on the effect though and isn’t a larger color issue.

Since colorless can exile target creature for 7, could white get exile target creature for 7? Any white deck has access to scour from existence in legacy formats so I don’t think it would be a break at all

Just because we do something in colorless, doesn’t mean we’ll print the effect in a particular color. That said, we have printed “exile target creature” in white (for example Angelic Edict for 4W).

You've said a color pie break is when it undermines a weakness in a color. What of Scour from Existence and Universal Solvent, which let any color remove any type of permanent? Or in general, there's a whole lineage of artifacts that let e.g. green deal damage to creatures or give them flying. If the justification is it's less efficient than what other colors have access to, that could also justify Desert Twister? (Which sounds right to me: that weaknesses are relative rather than absolute.)

Most players do not understand power level. The difference between a color doing something, in the color, and not, can’t be differentiated solely by mana cost because the majority of players won’t get where the line is and will just read it as something the color does. Generic cost artifacts can hit the line because it’s not communicating that a specific color can do something, and we can set the mana cost to keep from causing practical issues. For example, destroying any permanent in generic mana always costs at least 7.

"Being a color pie break requires you being in the color, not whether or not a deck can play the card." (From an earlier answer.) This is something that took me a long time to understand, and I'm still not sure I fully grok it. Desert Twister and Scour from Existence both let green remove permanents, but only Twister hurts the game. So it's more than an issue of competitive balance. It's as if the colors have personalities, and color pie breaks are out-of-character actions. Is that at all close?

We set limits for colorless abilities. For example, it costs 7 to destroy a permanent. This keeps colorless cards from undermining the color pie. Color identity is more than just what can go in the deck, but what that color itself can do. If we printed colored cards doing off color things at colorless limits, it would set bad messages about what the color can do. Most players aren’t good at telling rate, so a colored card at a bad rate just says, “Yeah, this color can do this.”

Is the reason Green can't have Desert Twister but a green deck can have Scour from Existence is that by putting an effect in a color puts it on the path of becoming normalized and costed cheaper?

The color green can’t do it. Artifact and colorless sources are not green.

So something that doesn't make sense to me is your statement that it's ok for colorless to do things at a high cost that a color can't do. So Scour From Existence is ok but Desert Twister (or let's say a theoretical 7 CC Twister) is not ok. But mechanically I can slot Scour into a mono green deck. I thought that "not undermining a color's weaknesses" was a mechanical thing, and colorless does just that.

Making a Green card at any cost says “Green does that” where making a colorless card does not. Yes, you can put colorless cards in your monoGreen deck but it is not conveying anything about what Green does. Green having to go outside of Green, even to colorless, stresses strongly that the thing is out of color pie.

Thematically speaking, I see a lot of cards that could fit a Kiora centered deck. A lot of Simic Guild cards seem to cooperate nicely. But how do I justify things like Phyrexian Infect or Eldrazi Scour From Existence?

Thematically speaking? You don’t.

How is Scour from Existence not a color pie violation then? It allows red and black to deal with enchantments, one of the main weaknesses of these two colors, though admittedly at a greater cost.

You are confusing “can be played in the deck” with “is in that color”. Color philosophies are about what that color can do. Colorless cards, not being in that color, have no impact on what the color can philosophically do.

Why doesn't Scour from Existence break the color pie?

Just as with artifacts we let colorless do things at a high enough cost.