We didn't know that the writer had "head hopped" and "filtered" and used too many "ly" adverbs, etc. And we didn't care, because we didn't know we were supposed to.
A reader doesn't care about the violation of the rules for their own sake. But they do notice things and can be turned off by them without knowing why.
The reader may not say, "That story bugged me with all the head hopping." But he might say, "Jeez, I had trouble keeping all the characters' thoughts straight or in relating to any of the characters and I gave up on trying."
Filtering tends to distance the reader from the character. If there's a lot of filtering going on, most readers won't think of it as such (I didn't even know it was called filtering until recently), but they may notice that they didn't feel as "close" to that character as they did to some others they've read. Maybe it won't bug them, or maybe they'll stop reading because "the character just didn't grab them."
But you are right that many "rules" in writing are really guidelines, and there are situations where they can be bent or broken. I doubt most of us could successfully write a novel length work with no filtering at all, nor should most of us try to.
I think sometimes those of us who are gaining experience as writers and are past the raw beginner stage but are not yet experts (and I definitely include myself in this), will sometimes jump on things people do without thinking about whether we are neutering someone's uniqueness or tone as a writer or mucking around with character voice. Sometimes the writer
wants a sentence to sound weak and tentative or passive or repetitive or filtered.