It's not a bad trend, I would say. Highlighting the humanity (so to speak) of the person on the other side of a heroic tale can be, and often is, incredibly effective. It certainly makes a pleasant change from the unbelievable villain who is evil for evil's sake.
You know, the one who plainly knows what they're doing is wrong or evil, but will do it anyway because they're evil, damn it!
But I don't think that making your villains sympathetic is necessary.
What you must do is make them believable.
A believable villain is someone who doesn't believe they are the villain. I feel that a believable villain is someone who genuinely thinks they're doing the right thing; even if their philosophy of what is right and wrong is horribly twisted. Neo-Nazis believe they're valiantly defending the "white race" from the threat of the...uh... other races... or something equally as inane. And they're willing to resort to violence, and genocide, to do it... because heroes slay the enemy, right?
Look, I said the philosophy could be wrong and twisted. That's about as wrong and twisted as it gets. But the important thing is, they believe they're doing the right thing, at least by the people they think are the worthy.
Ugh. I feel like vomiting.
Sometimes, believable villains are not in the least bit sympathetic. They don't have a tragic backstory that made them this way. Sometimes, they're wealthy, have all the advantages, and are just fucking arseholes, you know?
I tell you what, I don't have much sympathy for the real life villains. Neo-Nazis can go fuck themselves. They're awful, their philosophy indefensible. But they believe they're in the right.
I'm not fond of the politicians who are literally fighting against human right from trans folk and other members of the LGBTQA+ community, those who are making life difficult for the poor for no reason, those who are happily destroying our planet. I don't understand how they could possibly justify what they're doing. It is abhorrent to me. Still, they think (or have convinced themselves) they're doing the right thing. Somehow.
In Skylark, my (as yet) unpublished science fiction, the villains are pulled from real life. They're people who fundamentally believe that humanity's biggest threat is the alien species they're newly allied with, and so they work to undo that alliance and rid earth of the aliens. They're wrong, but that is the worldview they're operating from.
So, you, as a writer, do not necessarily need to craft a sympathetic villain to make your villain work. Make them believable. Or rather, make them believe they're doing what's right, even if that belief is utterly unfounded, or based on some terrible, twisted philosophy.
You don't have to feel sorry for the villain.