Eh, that just goes with the territory. To alleviate that somewhat, steal ideas/motifs from multiple sources across different genres. That way, instead of being called an asshole plagiarist, you'll be called a mo-fo genius.
Windows 98. Yeah, I'm old. It was a time when the internet was the Wild West, and anime was a novelty, and Toonami was a thing on Cartoon Network, and Sailor Moon and DBZ were on weekday afternoons. It was glorious!
If you want to write a longer narrative, try adding more characters, specifically more POV characters. That will add more chapters to your story. I think I have the opposite problem from you. All my stories keep turning into these big-ass doorstoppers that take me forever to write. One story I'm...
Well, there are two kinds of writer's block. There's writer's block, and then there's burnout. If it's writer's block, then you can fix it by tackling something new. If it's burnout, then you need to take some time off and rest.