There is a certain amount of truth in the thought that colours come and go, in and out of fashion. But equally, there are classic colour schemes which always seem to work. And some modern colour schemes would look out of place in a Victorian property, just as some Victorian colour schemes wouldn't work in a modern flat. Whether or not any of that matters to you is entirely down to you; just as in clothing, music and many other fields, some people are totally obsessed with the latest fashions, others are mildly interested, and some just stick to what works for them.
Personally I fall into the "mildly interested" group when it comes to colour fashion. I'm fascinated by colour, but not to the extent that I repaint my own house from top to bottom every time this or that paint manufacturer or interior designer declares that such-and-such is this year's "must have" shade.
According to Dulux, many of this year's colours seem to be very "earthy".
They describe it as being subtle and versatile, and given the other colours they claim are "on trend", I can see where they're coming from. You could combine Copper Blush with earthy browns and terracottas for a Mediterranean feel. You could mix it with pinky-red colours (either paler ones or stronger ones such as Pink Nevada 1, or use it as the highlight colour with greys such as Dulux Night Jewels 5. So it would appear to be on trend (assuming you buy into their other thoughts about what is fashionable this year).
I guess the big question is whether or not it will prove popular. For me personally, I've always liked terracotta shades in the right setting, but their popularity peaked in the late 1980's. I honestly can't remember the last time I painted anything using a colour that would be classified in the "orange" segment of the colour wheel. Maybe it's coming back in - that happens all the time, colours and styles that were in vogue 20 years ago suddenly reappear. Maybe Dulux have got it right, maybe not. Personally I'm not convinced yet, but time will tell....
I do think they've got it pretty right with the trends in neutral colours though. Greys are still hugely popular and are so versatile. And now people have got used to the idea of brown shades being acceptable as neutrals, I am seeing people being willing to experiment with stronger, darker shades. Not everyone, and that's the point. There will always be the "dedicated followers of fashion", those who seize the latest trends and adopt them instantly. Just as there will be those who take their time before accepting changing fashions, and those who are happy with their own sense of style and remain content doing their own thing.
And the good news? On this occasion, everyone's right!
It's your home, decorate it the way you want to!