Remove all the "A Diverse World" maps and make it impossible to make maps with names containing "Diverse World"
0xGG
I can't believe we still need to point this out. It took months of many members of the community pointing this out on the #feedback channel to get GeoGuessr to delete the largest fake "A Diverse World" map...when it reached the top 10 maps by likes. The smaller fake maps are now catching up again. Even if you are, as you say, discussing how to approach this problem in general, which for some reason is a discussion that requires months of time, this is a pretty easy temporary fix. It's to GeoGuessr's benefit to not have the fake ADWs around—nearly all of them are low quality, polygonal maps for which when a novice player plays it because they think that's the good map to play, they'll think the quality of GeoGuessr has gone down.
MiraMatt
Some data:
There are currently 259 maps that are titled exactly "A Diverse World".
* 328 that start with "A Diverse World" - often including tags to make them sound like an 'updated' A Diverse World
* 746 that have 'Diverse' and 'World' in the title
* 1654 with 'Diverse' in the name (although many are clearly not confusable with the original)