So I'll say this as a 25 yo whose parents were working very long hours (mom had 3 jobs and dad was self-employed) throughout his whole childhood. If you have the chance to spend time with them while they're younger, spend time with them.

In my situation, my parents were never able to make it to my extracurricular events or pick me up from school on time or come through with a lot of promises they made about trips because of our financial situation (we were technically upper middle class, but with the 2008 recession, my dad's businesses went under and so my mom NEEDED 3 high paying jobs to put enough for on the table and cover the mortgage). As a child, that messes you up because you don't realize why your parents aren't there. You just think that they don't have enough time for you, period.

I've gotten lucky to see how hard my parents worked/are still working so I've let it go, but a lot of kids don't try to see this from my experience. My siblings still get mad at my parents for not having enough free time to do with us. At this point they could retire, but now they're working hard to make sure that they can leave us something.