That is another hunch that I was considering posting but personally I'm skeptical of this. While immigration reform may have fell on its face due to opposition from tech firms, I find it hard to believe the Trump administration would conceive such an effective means of targeting them.

It stands to reason that they recognized NSOs/ISOs being used heavily (perhaps more than anyone else) by tech firms but this just seems like a recognition that wealth taxation woefully needs reform. The estate tax is being retired so this seems to balance it out.