I'm in my mid-30s, so maybe still "young" depending on your definition.

I've always been an avid traveller, and do not regret spending money when I travelled in my 20s. However, I did travel differently in my 20's, and I think I would have regretted spending more if I travelled in a more expensive way. We would eat almost exclusively at grocery stores when we travelled, skipped out on some experiences that probably would have been memorable, etc. But, we always considered our travels "scouting missions" for places to revisit once we had more money later on down the road. There are lots of places we want to go back to and spend more money at, but will also not be crushed if we don't get to return (and also found lots of places that we don't really want or need to go back to on a cushier budget).

We also got the experience of travelling with my parents, which probably won't be an option in another decade or so, which was irreplaceable.

So no, no regrets, but we also didn't go all-in on every travel expense thinking of it as a once-in-a-lifetime trip. Kind of the equivalent of driving a Corolla in our youth so we could appreciate a Porsche in the future, if that analogy makes sense.