My husband and I are 68 and have developed some issues that will affect our mobility more and more as we age further, so our approach has been to try to do some of the more challenging trips while we still can, realizing that those we don't do now, we may never do.
So, in 2024, we went to Taiwan, Vietnam, and Cambodia. Walking around the ruins in the heat was a challenge.
In 2025, we went to New Zealand and Australia. (Challenging mainly because of flight length and because of snorkelling in the Great Barrier Reef.)
We just returned from primate trekking in Rwanda, and, if I'm being honest, we probably left that one a couple of years too long. I'm not sure we could have done it in another year.
We also travel Premium Economy on flights over 4-5 hours, bid for upgrades to Business Class when we can, and break up our trips whenever possible, although our return trip from Rwanda consisted of 2 flights, totalling almost 24 hours of travel, including airport time. (We did stay in Montreal for the weekend instead of flying directly home to Calgary, which would have added another 4 1/2 hours of flight time and 2+ hours of airport time to the trip. And we did successfully upgrade to Business on our flight from Kigali to Brussels.)
We still travel carry-on only, but that might change as our ability to carry bags up/down boarding stairs--fairly common, in our experience--and hoist bags overhead diminishes. We'll never travel with extremely large bags, though. I much prefer travelling light.
We still prefer public transit.
We do look for places without too many flights of stairs now, although a couple of flights is still okay.
We are more likely to book an extra night at our accommodation if we have a flight that arrives really early after a long flight. (We didn't do this on our recent trip, though.)
We are more likely to book some kind of short stay accommodation if we have an evening departure. Some airport hotels will do hourly bookings now. We'd rather wait in comfort and privacy.
I'm more likely to use just my phone for photos, to keep down the weight of what I carry around all day.
I definitely have to pack a pair of reading glasses with me now. I can no longer get by without them.
At some point, we might have to consider group travel, but I really don't think I'd like it, so I'm not sure.