Punchline: No. And none of your examples contains a clear cut passive.
First of, "betroffen sein" can have two meanings.... to be affected directly and to be affected emotionally or in other words to be sad.
Which one it is is made clear by context and phrasing.
This is not a passive but "werden" in its capacity as "to become". I understand this to be the sad-version as the direct being affected is not phrased as an ongoing process. It always comes as in combination with "sein".
The sentence is a colloquial statement about habit with "viel" answering to "how often"
People became sad (due to some events) often.
Again, this is not passive. I mean structure-wise it is but it doesn't feel passive. It is "to become".
The "sehr" modifies the "betroffen" in this case. Again, I perceive the sad-betroffen, since "sein" is missing.
People felt very sad.
Now we have "sein", so it is harder to tell which "betroffen" it is. The "viel" however does the same as in 1a... it is a colloquial indication of frequency.
The people were sad a lot/affected.
Is it passive? Well, what's the difference between a participle-2 adjective used in combination with "sein" and "Vorgangspassiv" to begin with (hint: it is rather small... non-existant for most verbs)
This is pretty much like 2a), only that "sehr" modifies "betroffen". I don't know which "betroffen" it is but I tend to say "sad"
People were very sad.
Is it passive? Asnwer: Does it matter?
Now, since all examples were pretty much the "sad"betroffen,let me give you an example for the other one. Since we need the verb "sein" in the sentence to not have "werden" sound like "to become" we can only build "Vorgangspassiv/Adjective-assignment"...
Das Media-Departement ist von den Umstrukturierungen nicht betroffen.
Lastly, one general thing: "viel" does not modify adjectives.