difference between "opinion" and "input"

Question

What's the difference between "opinion" and "input" (when it's used in the sense of "opinion")? Are there any subtle connotations that a non-native English speaker would not notice and, thus, make a mistake?

Webster does a good job explaining out the subtle hues in meaning between synonyms, but, sadly, for the group of synonyms of "opinion" it didn't include "input":

Is it like "input" is sort of more technical and more suitable for a discussion, in which more than two people involved? For example, if the text below implies a discussion done by a group of specialists in some area, then "input" would fit better than "opinion":

He would never interrupt me or change the topic of our discussion and would always wait for me first to address him directly before he could share his own input on the subject matter or provide his answer.

or not?

Answer 1

Question: Is "input" is sort of more technical and more suitable for a discussion, in which more than two people involved?

input doesn't have to be technical, but as @Kate Bunting commented, it's more suitable in a group discussion, although it can be used in a dialogue as well.

Question: Webster does a good job explaining out the subtle hues in meaning between synonyms, but, sadly, for the group of synonyms of "opinion" it didn't include "input"

opinion implies the need to deliberate on ambiguities, and that's why in the synonym discussion you quoted, input is not included. Instead, opinion is compared with other words signaling different ways ambiguities are dealt with in the deliberation: the subject doing the deliberation, the process of the deliberation, the result of the deliberation.

In another sense, input is more general than opinion and can pertain to ideas that do not directly addresses the topic, thus input may not include deliberation. Let's say someone asked me what's the best car on the market. If I don't want to disclose my opinion (say, Toyota Camry), I can say: "I cannot give you an opinion, but my input is for you to go to edmunds.com."

Or more specifically: "I cannot give you an opinion, but I recommend consulting edmunds.com". In making a sentence we always want to be as specific as possible, so if you can be more specific, opinion is better than input.