Even the short stories you see in magazines now might have been written and bought a year or more ago. No way to tell.

Back to topic... I read SO much. I still feel this aspect is a shortcoming to many writers. If you want to sell short stories... You need to read them. If for no other reason than to get a feel for editors tastes. And by "dated" stories... Well sorry but give me a piece and I'll tell you within a year or two when it was written. If I can't I'd consider it a timeless piece and has a better chance of getting published. I'm not telling anyone what is right and wrong... Just paying forward an IMO overlooked area we can improve.

I guess it is a matter of what motivates one to write. "Professional" writers -- those for whom writing is a business and their means of income -- may need keep very attuned to these trends in what sells. Similarly, I suspect this is true for any author seeking to be "professional." Their purpose for writing is to be published. For both, perhaps, the ultimate goal is that rare achievement of writing success where one's name sells one's writing. Then one can have the freedom to write whatever one wishes.

I prefer to write whatever I wish. Now.
Don't you?

Admittedly, I have no expectation nor need for writing to be a means for earning a living.
I write only because it is fun.
A lotta work, but fun.
I am also awed by the process. Sometimes I have no idea where the words are coming from, or why my characters suddenly act a certain way or say what they do. Crafting a story is not aligning girders and dry wall to someone else's expectations, but whittling wood to free the form I imagine is within it. The former will sell, but perhaps the latter will amaze a few.

I see the value in publication as merely fulfilling the purpose of being a story teller: having people to tell the story to.

Bent Tree, I see your point, I have been told that by at least a couple of pros. Which is why I waited a while to start on my first UF book. That fad would probably fade before I get a novel written, checked over and sent in. If not then it would be over by the time an editor would decide they liked it, if that ever happened. But it's not fading, it's still growing so since that is what I wanted to write about I did. Twice at once.

But there are certain areas in Science Fiction and Fantasy that seem to be always in style. Space opera is one. The number of books may drop but it never goes out completely, there are always a few best selling authors. In Fantasy there is epic fantasy- like Lord of the Rings. There's always some books in that area that sell a lot.

And on the other hand for those who want to be pros, it is always a good idea to keep abreast of changes in your business. Not only what type of stories are selling but things like epublishing and which publisher may be going out of business, etc. also.

But it's always up to you what you write. Even in an area that has been mostly passed over yours might be the book that gets it going. Like I to blame or credit as the case may be. , Jim Butcher for the UF fad. He, at least, helped to push it along. David Weber helped Space Opera sell, I think. It wasn't just him but he made an impact on it. So again write what you want to, unless of course you have a contract with someone who wants a certain genera of story. Or you need money and you know what is selling. Some pro writers have done that over the years but it's still up to you.