I don't think you do.
It hasn't 'evolved' at all, it's just different and the fact that we're still getting games with isometric perspectives disproves your theory about it just being a product of it's time but feel free to keep thinking that way.
I mean you're wrong, but it's ok to be wrong I guess.
I'm out
Sorry, these days most people do see turn based as something as a thing of the past (they assume it's more cause of technology we don't need to rely on that but can have action and good graphics <- I was explaining to some one that Fallout 1 and 2 don't look that dated cause of their style of gameplay they could do better graphics on it).
What they don't realize it is based on paper and dice style games.
One could argue that paper and dice style games are that way though cause they really can't simulate real time action better than that in the real world. And now that we have the tech we can simulate it more being real time action vs. letting the dice decide if you succeed or not (at least in a computer game).
Really though, I'd say it is still fun to play the turn based games (I'm having a helluva lot of fun with Fallout 2 right now. Actually prefer it to 1 which I couldn't get into as much. Too bad I didn't get a chance to try 2 when I was trying to get into fallout cause they hadn't put it on Mac yet and I didn't think they would so it was a long time before I found that there was a Mac version as probably by the time they came out with the Mac version I had moved on to other things).
But, I'm sorry, I like what Bethesda did to Fallout gameplay wise. I love the exploration more (not having to just hit from point to point but allowed to enjoy the travelling in between points and seeing the random stuff on the way) and I do like the gunplay (ok, of Fallout New Vegas. 3's gunplay was not so interesting so I did use VATs a lot. For me I really like ADS much better, feels more like aiming a gun rather than just pointing and clicking on a spot. And I like games that simulate things better... for me I think I want a game to be a good simulator more than anything else... I want to simulate being in a post apocalypse world and trying to survive).
Yes, 2 did have a lot better story (and probably easier cause they could use less resources on developing the game and more on story). But I think Vegas was a great compromise between having a good story and the gameplay I liked a lot. In fact it's my GOAT (and also obviously my faovrite Fallout game. I think 2 might follow Vegas though). And sorry, New Vegas wouldn't have happened without Bethesda changing Fallout's gameplay style.
Not to mention that Bethesda I think brought Fallout to more people's attention. A lot to most of the Fallout fans know about Fallout from 3 than from 1 + 2. Which is why I compare it to GTA for that aspect (cause GTA 3 also is what got GTA really popular. The top down ones showed the potential and they changed the gameplay and got more people into it. Most people today would probably be shocked at what GTA started as).
But really what makes Fallout Fallout is not just the post apocalypse setting or the dark humor, but the whole idea that culture never evolved past the 50's. That's what really sets Fallout apart honestly. For one the 50's was when you had the big nuclear scare so it really fits with this post apocalypse future idea and also, the 50's was seen as quite cheery so it makes for an interesting backdrop to see this cheery culture style in such a dark setting.
(Which is also why I am really against Fallout being outside of America. Cause American 50's culture is a big part of Fallout).