Implementing a way to seperate artists with the same name has been suggested over on the Ideas Exchange here.
If you would like to see it implemented as a feature, I would suggest you add your kudos and comments there.
Okay, kudos for having this as an "idea". It's in the system so it can be fixed.
Going to the "idea", I discovered that this "idea" is almost a year old with many kudos and there's been no action on this by Spotify! This is basic artist catalogue functionality. Why is this not being worked on? It affects all Spotify users and fixing it would increase our enjoyment of Spotify.
It could be being worked on, since Spotify development is done behind a curtain of mystery I guess we will never know what they actually have in development. With that in mind, it is a little bit of a rhetorical question pointed at me, since obviously I can't give you the answer but pointing people the the Ideas Exchange to show this feature is in demand is something I can do.
You can also report any instances where you see 2 artists on the same page directly to the content team by following the steps outlined in this post from which I am guessing they pass that information over to the record labels.