RonJohn comments that its use is a flag that the question is probably off-topic. That sounds like a tag that will not be used by people who know what it's for.
"Probably" <> "definitely".
In a nutshell, there are cases where accounting questions can be on-topic, but they are generally not.
Questions at Personal Finance & Money must relate to personal finance. And some people do use accounting for their personal finance. So, we need a tag for those instances.
But the mere presence of a tag for 'accounting' doesn't imply every accounting question is on-topic — only some of them are. Yes, people will misunderstand and ask accounting homework questions anyway, that have zero bearing on their personal finance. That's when the community should vote-to-close.
I wish Stack Exchange had a feature where we could warn somebody that's using the tag on a new question to make really, really sure that their question is appropriate for the site.