possible plot hole?

There are a lot of people out there in their 60's that still have parents alive and active into their 80's and 90's. Maybe not throwing bales of hay around, but certainly still capable of owning property. At either rate, the ranch seems to be well kept and maintained, perhaps "R Rambo", whoever that was, had some ranch hands to help out. Rambo said he had a father, maybe, he didn't know...so this Rambo could have even been an uncle or someone else he looked up when he got stateside.

You walked out at the right time anyway, because that was the end of the movie.

If I thought you weren't my friend, I just don't think I could bear it.

Why would you walk out?
I've never walked out on a movie no matter how bad I thought it was...

Rambo was not 65 but 59-60. He was born in 1947 and this movie takes place in 2006 or 2007. His father would probably be in his early 80's then.

Btw, i always thought it would be cool to see a mid credit scene where Rambo rings a doorbell, the door opens and we see either Kirk Douglas or Clint Eastwood in a short cameo as Rambo's father. Actually it would be cool if they got Kirk Douglas to play the role, as he was the original choice to play Colonel Trautman in "First Blood", before he resigned at the last moment.

What do you mean you walked out?! That's the end of that movie haha. It is literally the last scene.

Yup, its a plot hole. To be fair though, this is the only plot hole in the franchise

They shot an alternative ending which an elderly man with a cowboy hat is sitting in the porch and he gets up when we he sees Rambo approaching!

I think the theatrical ending works great.

It's not a plot whole. I used to work for a rancher who was in his late 80's. He was up at the crack of dawn every day, doing chores and working out the horses like he was half his age.