So while showcasing the brand-new vector tiles, they accidentally also showcased a pretty significant bug? Should have picked some city with non-latin script that's written left-to-right... er, maybe Athens?

They released them for testing purposes, originally on a test server and now a soft launch on OSMF hardware. https://community.openstreetmap.org/t/vector-tiles-on-osmf-h...

The author of the blog post chose an area that doesn't render well. The various issues are being flagged in the relevant repositories as they are found.