I completely agree, and I don't understand what, aside from its historical significance, people can point to that suggest it was a good logo. I think it's a little visually complicated, I don't think the colors harmonize, it's not transcendentally simple like the Apple logo or the Nike swish, the choice of font and arrangement of letters isn't doing anything for me. and I'd like to think that I'm the type of person that would be receptive to rationales for why logos are the way they are. Not that I'm an expert, but I followed conversations on flag design, I've read about the Twitter and Pepsi logo redesigns, the Obama icon, etc.
The best rationale that I can think of is that it looks like an artifact of outdated 90s design, but was produced in the 80s, and so was in a sense ahead of its time, which counts for something, at least.
Rand would argue it looks dated because NeXT is dated. It’s a relic. The logo reflects the association to the reality, that is, NeXT is an old idea from yesteryear.
The best rationale that I can think of is that it looks like an artifact of outdated 90s design, but was produced in the 80s, and so was in a sense ahead of its time, which counts for something, at least.