If anyone out there wants a massive dataset to train these things, the entirety of Spain's LiDAR scan is freely available under CC-BY 4.0 license: http://pnoa.ign.es/presentacion

As is Finland's: https://www.maanmittauslaitos.fi/en/e-services/open-data-fil...

For Helsinki area there's also a lot higher resolution data available: https://hri.fi/data/en_GB/dataset/helsingin-laserkeilausaine...

Very cool. Thank you for sharing this link.