There is a meaning of 'good for' meaning it is a useful tool, but you never use it for a person except in a very
insulting way.
He is good for carrying the luggage but little else. Don't trust him with anything more complicated.
There is even the adjective/noun - a good-for-nothing. But never use 'good for' about a person.
Quote:good-for-nothing
/ɡʊdfəˈnʌθɪŋ/
adjective
(of a person) lazy and feckless.
"his good-for-nothing son"
Similar: useless worthless
noun
a lazy, feckless person.
It works for
inanimate objects.
This tool is good for picking up leaves.
This programme is the best for editing video.
That is one of its uses. I find it useful for that task.
But people are
good at doing things, even if that skill is useful.