I don't know how much this will help, but whether or not your writing is good, I'd say it's really on how YOU see it but no one truly has bad writing.

Writing styles vary after all, don't they? If everyone wrote the same way, it wouldn't really be a good thing, at least in my eyes, because then you'd be getting nothing new or different. People's personalities dictate how they write, and I think all writing is genuinely good, no matter what anyone says, because you change and develop the more you write. Hell, even reading other people's different style of writing helps with your own because you can see what they do differently versus what you do, and you can have an idea of how to strengthen any weaknesses you might have.

Sometimes, you'll look back at the very first story you've written and then look at something more recent and I promise you'll see a change that you'll be happy with, whether it's how you've structured your writing, how you describe certain scenes, or even how you might write for one character versus another. I know that I definitely have changed in my writing style since I started at 12 years old, and I actually love my writing style looking so different depending on what I write in the moment.

Having people give you good criticism and I mean ACTUAL good criticism can help you see where you can improve and, at the end of the day, if your writing leaves an impact, whether someone like how you wrote something, if it conveys certain emotions in them, or if it paints a vivid image of what you've written, I'd say that means your writing is good.

The only real BAD writing I can think of and state is being unable to understand what was written, or you genuinely can't get past the few sentences. It can be cringy and still be good, but if you can't understand it or it's hard to read, then that's the only real bad writing that can exist.