I agree with above. FO1 and 2 were legends (never tried Brotherhood or the weirder spinoffs.) Part of this was fairly faithful adherence to the systems and, I guess, philosophy of the original paper RPG.
New Vegas was great, just lots of fun, and fun to play again in different ways, which is a sign of a great RPG.
FO3... I don't think I really tried the DLC and I'm not sure I ever actually finished the game, but I had a high tolerance for TES: Oblivion and this was largely Oblivion with mutants.
FO4 they clearly wanted to make a shooter and not an actual RPG. I gave up on it after a few hours. Even in that time it really wanted to beat you on the head with politics too, which was a turnoff, and not really in the spirit of the source material.
My understanding of this show is the writers have already expressed disdain for the source material and any fans of it. It's already sounding like the Witcher or other shows I've memory-holed out. I'm sure it will have Ink Spots songs and bobbleheads but the trailer sure makes it look very shooty and otherwise uninteresting.