why so much EA for forex and none for Stocks ?

 
I'm a stock trader, my broker software doesnt do autotrade from ParabolicSAR, my weapon of choice, so I started googleing and came across FOREX, while I was aware of FOREX, I was not aware of the intense level of math / EA.  Why all the programming of tools in Forex but not available for stocks ?  Should I move to Forex ?
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