Well, of course, there are exceptions. They make language interesting in my opinion.
Let me share with you some information on this topic, which is from a grammar book written by a world-renowned author:
4 much or very with past participles
When a past participle is part of a passive verb, we can put much or very much before it, but not very. He's (very) much admired by his students. (NOT ... very admired ...)
Britain's trade position has been (very) much weakened by inflation. (NOT ... very weakened ...)
When a past participle is used as an adjective, we usually prefer very. This is common with words referring to mental states, feelings and reactions. a very frightened animal (NOT a much frightened animal)
a very shocked expression
The children were very bored.
She looked very surprised.
Common exceptions: That's Alice, unless I'm (very) much mistaken. (NOT ... unless I'm very mistaken.)
He's well known in the art world. (NOT ... very known ...)
(Michael Swan Practical English Usage Third Edition page 381)
When much is a quantifier, it is used mainly in questions and negative sentences•Was there much mess?• I don't have much time.In sentences which are not questions or negative sentences, phrases like 'a lot of' and 'plenty of' are used instead• Kurama has a lot of snow (NOT Kurama has much snow).Much can also be used after too, so, and as• We've wasted too much time.• She cried so much her head ached.• Drink as much wine as you want.!! Do not use much before countable nouns. Use many or a lot of• There are too many advertisements on television (NOT There are too much advertisements on television).When much is an adverb, it is mainly used before comparative adjectives• He looks much older than 35.• Some people are much more fortunate than others.Much can also be used before some adjectives in questions and negative questions• She doesn't look much different with her new hairstyle.!! Do not use much before adjectives in sentences that are not questions or negative sentences. Use very• Tea and coffee taste very different (NOT Tea and coffee taste much different).Much can also be used before some past participles acting as adjectives• Education is a much discussed government service.• a much admired writer This use is mainly found in formal and literary English. much - Definition from Longman English Dictionary Online