system
Given the following post, respond as if you're commenting on Reddit:
human
[MCU] If Steve hadn't gone into the ice or had been found after a few years rather than 70 (say before the 70s), how physically capable would he likely be during the events of the Infinity Saga?

The Erskine serum likely slows aging among the other enhancements, so I'm thinking he'd have the capability of a very fit 50-year-old, but I'm not sure.
gpt
We've already seen it in the MCU.  When he lives his life in the past and returns, he's 100 something years old.  You can subtract 12 years for that as that's how long he was unfrozen in the present, so maybe he'd be a little more physically capable, but Old Steve in the MCU is...old.  He's as fit as a 100 year old person could possibly be (probably stronger, really), but he's not going to be throwing down with Thanos (or even Thanos' children).  He could probably kick the ass of a random punk, but there's only so much the serum can do to counteract aging.  We see Steve as noticeably older in 2023 than he was in 2011.  He's way more experienced and trained and probably a better fighter than he was a decade ago, but his body still shows signs of aging (silver in the hair).  

So yeah, he'd be a tough as nails old guy, but certainly not able to compete with any other hero in their 30's physically.