I actually came across a side quests today that rivals the better sidequests from New Vegas. Lots of ways to approach it, moral dilemmas, no clear cut right or wrong, discrete and significant endings and even a complete pacifist path where you can talk your way through. Oh, and someone asked me a science skill question, although there was no skill check, just a Fallout 3 reference.
If you look at a chart of Fallout 2 quests, you'll see that most of them at best have binary main paths, with a few having a middle path, so it really isn't much less complex. I think video games are like anything else, there's a lot of temptation to let nostalgia cloud your vision and decide that everything new sucks. But you miss out on letting yourself enjoy some great stuff that way.
I don't actually mind the radial dialogue tree, but if you're going to do it, go all in. Dragon Age Inquisition did it the best, I think. There are tons of options, branching paths, choices specific to your character's knowledge, alignments and background. And clear indications of your each choice's tone when that matters. Fallout 4's system feels like a stripped down version of that with some charisma checks. Still good, but a missed opportunity.