Earlier quoted context omitted.
I think they're just rebutting the claim that they must not have done anything interesting/meaningful if they were able to save so much.
No, that would be a stupid argument. The argument is that by saving almost all your after-basic-expenses income you postpone too many things which would be just much less interesting or cool when you are over 55. For example, traveling when you are in your 60ies and 20ies are two different things. In the latter case the cool things that you find/learn can positively impact your entire life. If you are in you 60ies it…
I'm still not sure I agree though. I know this sounds lame, but I think creating a stable life with people you really care about is worth a lot more than the memories of traveling all over the world in your youth. my parents lived well below their means for most of my childhood, and they now have a stable retirement with plenty of money to go on whatever trips they want. sometimes they take me with them. as far as I can tell, they are very happy to be able to do this now with their family rather than having the memories of doing it in their twenties.
something else kind of shitty to think about: the real return on a diversified portfolio over forty years is somewhere between 15x and 20x (unless something major changes in the world). $5k spent traveling at 25 could be $100k less when you're 65. depending how much you made later, this could be a meaningful amount you won't have to leave to your children or help them with their goals.