I don't think it's a "reputation" issue, more of a what they're being exposed to and what it's normalizing. From studies I've seen it's a significant percentage (from a random Google search [1]):

The review talked to young people aged 13 to 19 and surveyed 1,000 young people aged 16 to 21. Over 6 in 10 (64%) said they had seen online pornography. Of these:

    1 in 10 (10%) of nine-year-olds had seen pornography
    3 in 10 (27%) of children had seen pornography by age 11
    Half (50%) of children had seen it by age 13
    4 in 5 (79%) had seen violent pornography before the age of 18, with the report stating “young people are frequently exposed to violent pornography, depicting coercive, degrading or pain-inducing sex acts”.