Would you dump your issues on them or suck it up and deal with them yourself?

It obviously depends on the problems but usually the ones my mother would vent about where not super heavy "we're fucked" talk. She didn't openly declare that she wanted to vent but it just came naturally as we chatted. As one who grew up with "problems" dumped on me when I was younger, yeah I think it's ok. I'm sure there's some distinction with what you tell them but most of what my parent did was vent and I just nodded my head and listened. Kids are tough, I survived some really really rough shit and there are kids who survived 10x worse than what I did. I get that you want to avoid hurting them and it's optimal to do so but fuck off with your "parents should never do x" trash because every family is insanely varied.

You're using the terms emotional abuse and neglect retardedly, of course nobody wants kids to be abused and neglected. Of course everybody wants kids to be raised "right", nobody will claim they're for that but a parent venting their problems to a kid won't fuck them up more than the world will. Besides, handling adversity is part of growing up.

Don't want to vent to your kids? fine

Want to avoid it? fine

Do it naturally without noticing repercussions? fine

stop nerfing the world