No, it means that Trunp isn’t displaying the obvious cognitive deficits that Biden is displaying. Although he might be starting to.
I think people see Biden and Trump’s age differently. In Biden’s case it’s his mental acuity that is in question. I have never seen anyone comment negatively on his physical fitness. He’s trim, he can still ride a bike, he can jog a bit if he needs to - I’d say Biden’s physical health is as good or better than anyone 81 years old should expect. That’s not his problem.
Trump, on the other hand, still seems to be able to speak quickly and extemporaneously. He does not present as anywhere near as compromised as Biden intellectually. But he’s a fat slob with a bad diet and a florid, angy disposition. He could drop dead of a heart attack or have a stroke any time.
So the key worries about Trump’s age are likely the chance of a physical episode, while Biden’s problem is more about his mental capacity. That’s the way it looks to me, anyway.