How to return tile based on heightmap efficiently?

I am procedurally generating a world and for each position in the tilemap I call this function in order to get the tile type that matches the height:

 public static NaturalTile GetNaturalTileByHeight(float height)
     {
         SortedDictionary<float, NaturalTile> tilesByHeight = new SortedDictionary<float, NaturalTile>();
 
         foreach (var tile in AllTileTypes)
         {
             if (tile.MaxGenHeight > 0) tilesByHeight.Add(tile.MaxGenHeight, tile);
         }
 
         foreach (var tile in tilesByHeight)
         {
             if (height <= tile.Key) return tile.Value;
         }
 
         return null;
     }

For each single tile, I have to first create a sorted dictionary so that it's sorted by height. Then, I have to fill the sorted dictionary with the tiles based on height. Finally, I compare the height with each tile in the sorted dictionary, and since it's sorted by height it'll always return the lower-valued tiles first, which makes it work properly.

I feel like this is waaay too complex, even if it only happens once on world generation.

Any improvement suggestions are greatly appreciated.