Why mono colored icons for blender 2.8?

It’s as laughable as you wanting others to invest their time and money in doing what you want. Your points come across as entitlement, as do @Antaioz’s, not because you’re wrong or right, but because you’re not willing to get involved.

@jendrzych is a go-getter, he’s delivering work and causing change. And this is coming from me who also prefer the old icon style.

(Emphasis mine)
Why do they need to hear anything?
Stop writing text.
Show them. Make a mockup of what you think would look better.
Armchair criticism is not gonna have any impact.

This is open-source development. Since we’re in a hierarchy and have no stock / leverage in this decision, the best thing we can do is submit constructive criticism and move on.