WCAG defines different contrast rules for different font sizes. Thus "colors are colors" is not strictly true when it comes to evaluating contrast.
On an old CRT, this elements were probably huge (measured in centimeters) compared to how I look at them on my 4k screen now. And that matters when talking about contrast.
No, elements were not "huge" on old CRT's. That's just a fact. Absolute text sizes have remained approximately the same. Have you ever used one? Nothing has changed in terms of information density that would lead to higher contrast now being required. To the contrary -- increased sharpness means you might be able to get away with lower density.
On an old CRT, this elements were probably huge (measured in centimeters) compared to how I look at them on my 4k screen now. And that matters when talking about contrast.