Back in the day, it was all theater of the mind. It wasn't that I disdained miniatures, but back then being into miniatures meant buying lead, unpainted minis, and then painting them yourself. I simply didn't have the time, money, or inclination to get into them. And even if I had minis, I was never sure how to use them in play.
Experience with 4e made me much more confident playing with a map and minis, and the existence of pogs mean I don't have to try and maintain a big collection of them. Further, I play with my old group via Roll20, so having a map and tokens is a given. Conceivable we could just do theater of the mind via video chat, but it's just not quite the same.
I'm also more amenable to letting players interact with the game via the rules, rather than just telling me what they are doing. I tried running a B/X game in the old style, encouraging players to just declare their actions, and I would say whether they succeeded, failed, or needed to roll dice. I found that even if I did that, they tended to couch everything in "can I?" questions, and if I happened to use a houseruled mechanic, they'd ride it for all it was worth. I still prefer the older style, but I roll with it depending on the player. 5e just feels particularly good for this, since it's light enough that wing it with a clear conscience, but there's enough player-side mechanical meat that players who want that structure can have it.
One way I've changed is I'm much more amenable to random results. Back in the day, I often ignored random rolls because they didn't "make sense", eventually doing away with them altogether. Now I see unusual random results as opportunities.