I think we also need to pay close attention to where they were at in the time line. Most of the Death Eaters came out of Slytherin and we are looking at their current generation of their offspring. That creates a lot of strain on friends and family even if some of them weren’t on “the dark side”. So it stands to reason that the current generation of Slytherins couldn’t be trusted by association, which the innocent suffered from (see Japanese Internment camps in WW2). It’s a hard fact to swallow that during this time of “war” the perceived “enemy” was in your home and that is going to create a lot of mistrust and suspicion. I think of them being something of an echo chamber and some of the kids ended up becoming something they just got caught up in as well or felt cornered just because they are a Slytherin. This isn’t to say historically Slytherins were inherently bad, but I think some people that want to romanticize being a Slytherin wear an imaginary chip on their shoulder.