Nice post. Without going into too much detail on each of your questions:
How do individuals within the crypto community perceive the importance of decentralization ?
I think that decentralization is absolutely a core principle of bitcoin if not the most important principle. Money under the control of central groups / authority has always shown to be corrupted.
Does a higher decentralization index positively influence trust ?
If you mean that as a network becomes more decentralized people trust it more, In general I'd agree.
What are your thoughts on the role of decentralization ?
Decentralization is the key to censorship resistance.
And lastly, is there any website where I can see the chart ?
I wish.
My question:
Do some protocols work better with less decentralization / (more centralization)? If so what types of protocols would require less or more?