Cactus: battle-scarred or diseased?

[CarterBeatsTheDevil]

Rescued this cactus from chronic overwatering about six months ago: see photos. It's covered in rust-like patches and I thought it might be rotten at the bottom when I got it but the brown bits are as firm and healthy as the green bits and it is very well rooted having been repotted in the summer. Spines are very pointy and again very firmly attached to the plant. It did a bit of growing in the summer but obviously is not doing much now.

Is it just battle-scarred or is it on the way out?

It doesn't have spider mites, by the way, it's just still a bit dusty from the house it used to live in despite a lot of brushing 🙄

Mine looked like that for years before sending out pups and then dying. I don't think it is diseased.

That's reassuring, thank you! I've had a couple of people ask if it has water damage hence the question

It just looks like corking - cacti do this with age, nothing to worry about!

It's very hard to kill a cactus, i have lots, it will be fine.

As nan says, it’s fine. Looks very healthy. Don’t expect it to flower, enjoy it for its form.

Thanks, all! Very encouraging. I'm glad its number isn't up just yet.