For someone who wants to create heirlooms today, how would you go about it? Something sturdy and well made, but not so valuable that it’s tucked away into a box (like the Rolex in the article). The watch that I rock today (a smart watch) is well made but I don’t see it being useful in 50 years much less 20.
I don't think you should worry about usefulness at all. It's impossible to say what you have that will be useful to your grandchildren, but probably not very much.