tl;dr

We only query NE data starting at zoom 5, but the roads min_zoom also includes z3 and z4 values.

Let's do what we did for NE water labels (#1812) and clamp the exported min_zoom to the tile's min_zoom.

We should set:

• 3 to 5.0
• 4 to 5.1
• 5 to 5.2

===

This may be happening in more layers than roads...

• What did you see? Roads receive min_zoom values of 3 and 4 at zoom 5, but are only included in tiles starting at zoom 5.
• What did you expect to see? Either include the roads earlier, or cap the min_zoom of the roads at layer's start_zoom of 5.
• What map location are you having problems with? 5/41.162/-100.195
• Screenshot?