I don’t think that’s quite it (i.e. that modern amateur photo colorists are intentionally aiming for a 19th century tinted photo style).
The bigger problem is that real images have varying chroma and hue within single shapes, but actually mimicking that when coloring a black and white photograph takes a huge amount of skill, attention to detail, and work. You have to think about what the lighting was like, what material it was striking and at what angle, what lens filters the photographer might have used to capture the image, etc. and then you have to go in and painstakingly paint all of those fine gradations and textures in.
It’s especially difficult to do a convincing job with skin, but most materials are hard to color convincingly.
It’s much easier to apply color to whole shapes as a blob, but this looks terrible (very obviously wrong) when you make the colors very strong.
If you want to try for yourself, get a Photoshop expert friend to find some color photographs (without showing them to you first) and convert them to black and white, applying whatever kind of intermediate processing he/she desires as long as it results in a roughly photorealistic looking black and white image.
Then you try to photorealistically colorize the photo, spending as much time and effort on it as you want. When you have something you are satisfied with, compare to the colored original. It’s very likely that the colorized version will look pretty bad in comparison, even if it looked vaguely okay on its own.
The bigger problem is that real images have varying chroma and hue within single shapes, but actually mimicking that when coloring a black and white photograph takes a huge amount of skill, attention to detail, and work. You have to think about what the lighting was like, what material it was striking and at what angle, what lens filters the photographer might have used to capture the image, etc. and then you have to go in and painstakingly paint all of those fine gradations and textures in.
It’s especially difficult to do a convincing job with skin, but most materials are hard to color convincingly.
It’s much easier to apply color to whole shapes as a blob, but this looks terrible (very obviously wrong) when you make the colors very strong.
If you want to try for yourself, get a Photoshop expert friend to find some color photographs (without showing them to you first) and convert them to black and white, applying whatever kind of intermediate processing he/she desires as long as it results in a roughly photorealistic looking black and white image.
Then you try to photorealistically colorize the photo, spending as much time and effort on it as you want. When you have something you are satisfied with, compare to the colored original. It’s very likely that the colorized version will look pretty bad in comparison, even if it looked vaguely okay on its own.