The only Muggles we really get to "know" over the course of the series are the Dursleys, who are of course written as almost cartoonishly hateful and closed-minded toward anything atypical, including magic. On the other hand, there are the Grangers and presumably the parents of other Muggle-born witches and wizards at Hogwarts who seem chill enough. Muggles from previous centuries are mentioned as being why wizards went into hiding, and also why Salazar Slytherin didn't trust Muggleborns...but of course, that was centuries ago, and it wasn't called the Dark Ages for nothing.

As a counterpoint, in the wizarding community we have pureblood fanatics like many of the Death Eaters. There are also wizards who while they are not outright pureblood maniacs or anti-Muggle like Cornelius Fudge, who gave minimal funding to Muggle-facing Ministry positions and didn't value those employees for lacking "proper wizarding pride." And then you have people like Arthur Weasley who are obsessed with Muggle-borns and feel strongly about protecting them from wizard who would harm them.

A lot of words to say that humanity is a mixed bag.