My budget projections have my overall spending just increasing for inflation, but the buckets change over time. For the first 10 years of retirement (from 57 to 67), my projected travel budget is large, and my medical budget increases by some larger-than-inflation percentage. After that, my travel budget starts to go down, but my medical costs go up. It kind of gets at this idea of spending for pleasure early.
I have seen it both ways in my own family. When my parents retired at 57, they traveled quite a bit and did more things. Now, at 74, they still play golf and have quite a few hobbies, but they are home most of the time. Their general living expenses are much lower than 10 years ago.
My aunt and uncle are different. They also retired early. For years, my aunt worried about money and didn't spend much. They traveled in their RV around the country for a few months every year, but did that fairly cheaply. About 4 years ago, we went on a cruise to Alaska and they LOVED it. They have since been on 4 other cruises (including one in Europe and one that went from the US to Australia), and she went with girlfriends to Italy. At 70 (with my uncle being 84 and starting to show signs of Alzheimers) my aunt is realizing that they may have only a few travel years left, and after scrimping for years, she also realizes they have the money to do it.