Just my tuppence worth:
I’ve played since 1976 and still revere OD&D, though I suspect it’s as much the memories of the adventures and fun that I revere than the system per se. So I’m a “grognard” in the sense of the thrill of entering my first dungeon, sword in hand as Aelric the Warrior, and designing and stocking the Dungeon of Shadows for my first campaign.
What I’m trying to say is that our gaming preferences, grognard or whatever, are as much determined by where we were in our lives at the time as it is by where the game was at the time.
For me, I played a lot of Original and 1E between 76 and 84, whilst I was at school and university, with only rugby and partying as competition for gaming. Career and family kept me away from 2E, so I like that ruleset and culture less; not due to any actual intrinsic criteria, just because it spoke less to me.
I started playing again, with a great group, with 3e, so I’m keen on that gaming zeitgeist. For a number of reasons, 4e didn’t do it for me, but that’s just me (and my group). Maybe we were right, maybe wrong. Does it matter?
I love 5e and feel just as “grognard-y” about that ruleset and gaming culture.
I respect Gygax, Arneson, Jaquays, Kuntz etc for giving me the game I love and don’t go too deeply into fall-outs about systems, “skilled play” or similar debates, though I do feel strongly about inclusivity and disliked the Ernie stuff a couple months back.
The group I game with are all different, from a combat-oriented, skilled character designer, to a romantic role player, to a grimdark roleplayer, to an actor, to a tactician. All different, all friends and a very cohesive group.
It’s a great game, however you play. Enjoy.