I'm a junker, thrift store troller, and yes even a dealer in antiques and vintage stuff. (when the writing's not paying you find something that does and hopefully you love it.)
So... in that business we have a saying: If it exists, someone collects it.
I feel the same way about writing. If there's a sub-sub-sub-genre someone loves it. Someone once suggested I take a mystery audio drama I'd written and have the protagonist buy a B&B in tuscany and solve mysteries from there.
I told them... 1. do you know how many B&B cozy mysteries are written a year? 2. Tuscany? really?
In the cozy mystery field alone there are mysteries for : knitters, cat owners, horse owners, dog owners, B&B owner, amateur theatre, antiques dealers, thrift store owners, wine experts, small town newspaper reporters, chefs, artists.... etc etc etc.
You know why there are so many sub-genres in any genre itself? Because there are fans for it. It's like what the junkers say: if it exists someone collects it. If a sub-genre exists, someone loves it and its usually not just one person, it will build. If someone has a hobby they love it when the hero of the story is involved with that same hobby they go bonkers
the problem with trends is that they're over pretty quickly. A lot of times by the time you realize something is a trend and you write a new novel or comic there's a good chance the trend will be over before you're done. There's an unwritten rule in Hollywood, don't write what's breaking the box office now, by the time you're done the audience will have moved on. What you want to do is be the next big trend.
My thought is, create what you love and dabble in other things once in a while. A lot of famous authors are known primarily for one things, horror, fantasy, romance etc. but then you find out they write other things too.
Who knows, maybe you can make up a new sub-genre.