Mistakes in Deezer's genre categorization. How do can we fix this?

Going through the latest Deezer Month and noticing some odd inconsistencies in which genres artists/groups were categorised into.

The first worrying signs were when the Chordettes (the barbershop quartet from the 50s that mostly play traditional pop and doo wop) were categorised under Rock, I just can fathom why?

I then noticed that the main Irish folk and trad bands I was listening to (Gaelic Storm, Planxty, and the Chieftains) were being categorised under Punk. While I recognise that Gaelic Storm and the Chieftains have made more Folk/Celtic punk songs before, it is rare part of their discographies and I certainly didn’t listen to those tracks. I am not sure if this is the result of not have a Trad & Folk genre on Deezer, and only a Folk & singer-songwriter. 

Similarly the band the Mary Wallopers that also play Irish trad & folk, with a lot more Celtic/folk punk and rock mixed are simply classed as Alternative.

One more example I discovered was that the Osborne Brothers (a classic bluegrass and country duo) are categorised under Classic Rock, which doesn’t seem correct at all. 

I understand that one group/artist can traverse many genres and genres themselves are not a perfect system for categorising music, the borders between genres are grey and fuzzy. But if Deezer wants to collect accurate data on listening habits and then show off that data to us, it needs to get this kind of information correct more consistently or you are just left with crap data.

Is anyone else noticing the genre inconsistencies? How do you think that it can be solved? I am curious to see what other people think.

I personally think that expanding the list of available genres on Deezer to more prominent sub-genres would be a start. Maybe implementing a community system in which people can self report what genre they believe this artist or album (or maybe even song resides in). 
Or if Deezer even opened some odd internship/volunteer scheme for people with music or informatics degrees to go through bands and albums and re-categorising them using their own knowledge and research (and possibly using the self-report data as a guide to determine groups/artists or albums that really need a recategorization).