It’s been explained 100 times ad nauseam over the last two years. Go read comments from previous months’ updates if you want to catch up.
As for cross-platform compatibility, this should not come as a surprise because everything is written in Rust, and the libraries we use are already cross-platform by default in most instances. Supporting multiple platforms takes almost zero effort on our part. Especially when we could design something from the ground up that’s easy to adapt.