Being "on trend" isn't good UI design. But I can see how we got here. Through OS X and iOS, Apple's UI ethos became the gold standard in UI design. It was so well designed that it was easy to imitate and by simply adopting the core elements of Apples UI language, stuff became intuitive and usable without the designer needing to understand "why" something looked the way it looked.
And then came a new trend, the current trend, that appears to me to be rooted in nothing more substantial than a desire to replace the old with something new at all costs. And when the likes of Apple and Google fall for the same trap, it's nigh on impossible for fundamental UI design knowledge to make itself heard above the noise of a million designers advocating the new and pointing to Apple for credibility.
You can see that I don't like Material. I also don't like iOs's new UI language. It doesn't work. Ive seen no evidence that it's any more useable and I struggle everyday to make sense of software and tools that have adopted these new trends so anecdotally, I have to say to myself that we're going the wrong way.