[material-ui][docs] Component index icons should be blue, not purple

[oliviertassinari]

Steps to reproduce 🕹

Open https://mui.com/material-ui/all-components/

Actual

Purple

Expected

Blue

Why?

1. Material UI brand is blue, not purple. Bootstrap brand is purple.
2. Purple doesn't look great as a color, subjective to my view, but I think we can back this up with data when looking at the big picture: https://www.linkedin.com/pulse/what-most-popular-color-world-natalia-golenkova/ (I took men as 80% of the developers)

Going with blue would reduce the need to customize the color for developers when they are in a hurry. And improve the default look & feel (on average, some will prefer purple)

Linked to #40256

[danilo-leal]

I genuinely think the idea of a "Material UI brand" is super confusing; it doesn't make much sense to me. 😕 Doesn't the library follow Material Design's design specifications? If so, what's the point of having a slightly different Material Design visual that we categorize as "the Material UI brand"? If the goal is to implement MD as closely as possible, unless it hurts something super serious web development-wise, we shouldn't deviate from it (i.e., changing a core element such as the primary color). Our personal opinions about, for example, whether purple is a great color or not, are not as important; it's a decision MD made. In that sense, Bootstrap can do whatever as they don't intend to implement an existing design language as Material UI does with Material Design.

Material Design's primary color is purple (and the purple shades used in the illustrations were picked up from similar illustrations from their official site, as well as their official Figma design file).

[roy9495]

Can I work on this issue?

[danilo-leal]

Hey @roy9495 — thanks for the interest! I think we need to develop the discussion a bit more to evaluate if we even need to do something. Appreciate it. 👍