I wonder if ppl here are just speculating.....
Deri Lulavim are grown in Israel. This is a fact.
Although Egypt for the most part, stopped exporting Lulavim, some still has made it across the border. The export from El Arish in Egypt has been drastically reduced so that the Lulav shortage is REAL.
However, there are Lualvim exported from Spain for the past ten years or so. This has supplemented the shortage from Egypt.