I think interiors move on a much slower timescale than other things. Grey has taken about 15 years to cycle from 'fresh! fashionable!' to 'everywhere, the new neutral' to 'Ok this is a bit much now.'
And even then, I think grey won't be totally out, what will be is painting everything grey. We went for an off-grey carpet, even though I didn't really want grey, because it was basically the only 'neutral' option that was available to us, and I don't think its going to date immediately because its all what goes with it.
We have black windows and taps and fittings, which I imagine will be fashionable-ish (or at least not shameful) for at least another ten years. Our downstairs bathroom is a bit on-trend (encaustic tiles, bowl sink with black tap) our upstairs one is a bit 'basic' family bathroom (white tiles and fittings, chrome shower and tap) but I imagine will last longer. But again, I'm not imagining getting either of them redone inside the next decade.
I think you can swap in accessorises and not worry so much about the expensive bits. Our kitchen ended up being white, handleless, with wooden counters, its actually very similar to one my childhood best friend's parents put in in the nineties. I was in their house recently, they haven't especially changed it in thirty years and it really doesn't look dates - lovely dark rust paint colour in the living room, white in the hallways, their own unusual artwork on the walls. It was never especially in-fashion, so it doesn't look out-of-fashion.
Big 'trend' things - dark blue kitchens, very dark paint in 'snugs' - may signal strongly to a particular decade, but if you use paint for the most trendy things its easy enough to re-do. Go with what you like, OP: if its desperately on-trend, at least that means lots of other people like it too.