It seems likely that large internet businesses will probably pay to comply with GDPR.
Many small businesses, whose customers are often mostly regional anyhow, may decide that it's just not worth the cost of compliance.
https://www.nytimes.com/2018/08/22/technology/google-china-c...
But the EU, as a whole, is the world's biggest market and it is a common market in spite of legal and cultural differences between countries. So that's pretty naive.
And if companies think the "compliance cost" is too big, that's fine, it means they are leaving money on the table for their competition to pick up. The best outcome is actually the EU getting some real alternatives to US services that are deemed to be indispensable.
So personally, as an EU citizen, for companies no longer wanting to serve EU citizens, all I can say is don't let the door hit you on your way out.
