"vandalism"

If the owner didn't consent, yes, it's graffiti and vandalism. If they didn't say yes, the answer is always no.

"Commissioned mural artwork"

I'm pretty sure this is an example of the owner paying someone to do that, there's no way you could paint that quick enough

Yeah this was commissioned by the Glasgow government. https://www.glasgow.gov.uk/citycentremurals

art

Just because it's vandalism doesn't mean it isn't art and just because it's art doesn't mean it isn't vandalism, it works both ways.