First of all, many of us don't. I will say I don't know those "brands". Are they both fairly major universities? The US has lots of universities, and I think there's less "lower tier" ones in Europe. In fact, I had family move to the US for it.
These less prestigious schools, lower than state universities, which are often quite prestigious, have drastically lower entry standards. You quickly go from "needs a solid resume, with good academics, and participation in extracurriculars", to "accepts anyone".
Just because a University accepts everyone, doesn't mean it's "bad". I went to a good university with loose entry; they'd let anyone flunk out after the first year. That said, we look heavily at "pedigree" in the US. You need top academics to get into university, and usually have to be somewhat talented to meritfully advance (and we know who succeeded by merits). With pedigree you look at someone's full lineage and accomplishments. In theory you should look at what someone did in university and all these impressive sounding companies, but too often they just look at the letterhead!
I'm astonished by how reliably the "elite" are able to hold their position. In some cases, it doesn't even seem to make sense. For example there was this really insecure, power hungry kid for a Uni group, that wound up getting a pretty high position, quickly. He really clearly succeeded because of these insecurities, only to find that he was very wealthy.
I've become increasingly aware how people at higher levels in software have money, and seem to rise to the level of their wealth. Even I do pretty well, and I'm the grandson of an accomplished chemical engineer. Yet so, many of my managers are just a couple rungs above me, proportional to their wealth.
I've digressed, but I'd argue that in a country like the US, selecting based on pedigree, is not necessarily a bad decision. It's just shitty, discriminatory, even racist perhaps. Still, hiring the "elite" from society probably "works".