For me it wasn't. I transitioned into every edition up through 3rd. While fourth was the straw that broke the camels back for me, it was ultimately a sense of frustration I had that had been building up through third edition that led me to explore the older editions again. Won't run you through everything, but started looking at stuff like hex crawls again and reading the 1E DMG cover to cover. Checked out the OSR stuff and revisited 2E and read the white box and chainmail. Later I took a look at Moldvay (I grew up on Mentzer so Moldvay was legitimately new to me even though I was aware of it). I think what it boiled down to for me is looking back at my years of gaming (started in 86) it did feel like with D&D at least, something of what initially drew me to it had been lost. I thought that was nostalgia. But when I shifted to earlier editions, the game went back to feeling like it had before. There are a lot of reasons I think. I don' think it is some kind of magic bullet. But basically WOTC D&D is a very different thing from TSR D&D and I think I really am just more of a TSR D&D kind of person (and I did like 3E for quite a while, but eventually it became a bit frustrating to run, the flavor of 3rd and 4th just wasn't really resonating with me, and the mechanics weren't really what I wanted in D&D). Fifth edition came out, and I bought it, read it. Played a few games, but I had already realized I didn't really need the current edition of D&D to do what I wanted. I had my earlier editions and plenty of OSR stuff to use. And I mostly played other games anyways. So when I do play D&D, I like to go with the older stuff these days. I think it is preference, not nostalgia.