Here is an interesting essay, from what I have previously read and am reading now, it seems as though the real center of wootz steel production was in India. While blades may have been made in Persia/Syria it does not look like the raw materials were produced in these countries. The steel was produced in India and traded to sword making centers in other countries.
When Europeans recognized the superiority of Indian steel making technology they went about trying to creat a way to mass produce the same type of steel made in Indian so they could bypass the Indians. Many years of research into making high quality of steel by the Europeans eventually led to the modern steel making process that was directly responsible for the decline of traditional Indian steel manufacture.
Between the British desire to subvert the Indian steel makers and the now abundant supply of much cheaper European steel the Indian steel makers simply could not survive. The decline seems to be in the early mid to late 1800s.
http://www.ghadar.in/gjh_html/?q=con...eel-metallurgy