Depending on the show, they were colored differently to fit tv formats. Because of the way TVs worked, the brightness and graininess had to be factored into how the pictures looked. Now that we can see them in higher definition the images look saturated with color.

most of it is simply the result of the analog production process, and the losses inherent to each step. so you basically overshoot with bold colors so that it still looks decent at the other end.

older cartoons were produced with cells and photographic film. in that process you are literally blocking or transmitting light through both the cells themselves and the film both at the time they’re photographed and reproduced and eventually transferred to whatever electronic signal, which back then was also analog and had its own transmission loss.

every part of that process will result in a loss of both detail and ‘dynamic range’ so to speak because trying to pass a light through something while also having it be opaque is a conflicting process.

add into it all the other hand production methods, cell paintings, the relative quality of transfer technologies at the time, and yes the fact that its end was to show up either on a low res tv screen or a movie screen, which although capable of high detail theoretically, between multiple showings, flicker, and reproduction also be degraded.

in addition each color beyond just a flat reference color requires more attention to detail to keep consistency between artists etc.

we really take for granted how much the digital process has opened up for art reproducibility in the last 30 years.

Honestly it probably depends on the post production house prepared them. Everything has been scanned or copied to digital at this point. Sometimes that means the film was rescanned (if it still exists), some times its just just NTSC upscaled. Your black and white points may be at the whim of the junior color artists, which will partially determine the saturation and sharpness

There are several reasons.

Back then animated movies and shows were made by drawing directly onto paper and see through cells (basically like clear plastic sheets) this usually included the colors. Today even in the rare "hand drawn" cartoons that still exist, the color is usually done by computer.

The cells were usually the parts that would move or change the most, which is why if you ever noticed in those cartoons, you call always tell the part that is going to move, because the color looks a little different, and smoother.

So with that understanding here are some reasons.

1. Cells don't hold color as well as paper. Everything drawn on them looks a little dulled.

2. The clear part of cells stacked on paper dims the color of the paper below it slightly because there something inbetween.

3. Pigments (paint, markers, inks, dyes, crayons) are not perfect and are duller/dimmer than a computer generated image on a computer screen.

4. Pictures of pictures are never as vibrant and bright as the original pictures themselves. This is a little less true today as filters can boost colors of pictures afterwards, but this wasn't done back then.

5. Video tape used at the time, especially the cheaper video used for animation for broadcast TV has far less contrast and color range than newer cameras, and even those have far less than something made directly on the computer. TVs themselves could not show nearly as much color as today tvs so there wasn't really as much point in trying to go for anything fancier unless it was for a Disney quality feature film.

6. Batman TAS and several shows that followed it broke the mold of animation of the era by drawing on black paper instead of white. This gave it a far darker and grittier look that was copied by a lot of animation that came after it.

Our color preferences change over time, and new ones will always seem bright and fresh to us. There are professionals with advanced degrees and lots of artistic experience who spend their careers developing these and selling them to other companies--clothing manufacturers, artists, whatever. When you look at older palettes, like from your childhood, they always seem dim and dark even though they seemed bright and fresh at the time because there has been a continuous progression of colors since then and you have experienced this passage in time, personally.

[removed]

So 3 reasons:

1. Gamma correction - old school tube TVs work differently than modern LCD/LED screens. Specifically in the way the pixels represent color intensity. With modern screens, there is a mostly linear relationship between the pixel value and the actual color being seen so red 200 is twice as red as red 100. With tube TVs there was a curve, so red 200 might be 3 times as red as red 100, so you'd need to adjust the value down so that it looks right on the screen.

2. A lot of animation was done by hand - a lot of older animation was drawn on physical media, photographed, then assembled into a video reel. This means that the physical color palette used was restricted to what the artists had available at the time. The process used today is almost entirely digital and software can create basically any color you could ever want.

3. Style - in a lot of cases, the darker coloring was a stylistic choice. For example, scooby doo has very dark coloring to add to the mystery/horror atmosphere presented by the show. This is still done in some modern cartoons & animated shows.

A lot of it depends on how they were stored. If they were stored on a high quality master or digitally odds are the original content had more colors than the old TVs could even show you.

Old NTSC TV had a relatively narrow range of colors (color space) it could support. When we switched to HD we got a much wider range of colors. 4K has an even wider one. Many old TVs shows were stored with a wider color space than old NTSC TVs could display, so when you saw them on your old NTSC TV, it "clipped" the colors to what the TV could show. Which could have lead to them looking washed out.

Many old TV shows have been remastered for the streaming age, and now that we have TVs that can show us all the colors the show was originally created with, we get to see them. Some shows have even had the colors "corrected" to make them look more realistic/vibrant on modern TVs.