It looks like the Sakura foliage generation places leaves too far from the trunks. If you hover above a newly generated Sakura forest in Creative, you can see the leaves breaking. This issue existed in 1.16 as well.

Two possible solutions -- only place leaves where they will survive, or increase the allowable distance for Sakura leaves, like we do for some of the conifers. Anybody care which?

Also Japanese Maple trees, turns out.

Increase the allowable distance for sure.

It turns out only placing leaves where they survive is quite difficult for the Terraform shape API based canopies. However, Terraform also does not allow using extended leaves with small trunks. :sad_trombone:

We aren't going to generate Sakura biome by default in 1.20 so I may just put this off until then...