Why do you think wealth is a zero-sum game? Just because one country benefits economically means other countries have to lose? The pie is not fixed. It grows bigger when economies grow.
Countries with the highest economic freedom scores in the world have the highest GDP per capitas in the world. That's factual proof that friendlier economic environments make better businesses, which benefit workers who receive the highest incomes in the world. Hong Kong and Singapore are great examples.
No. He's using Nigeria's tax system as the only basis for choosing the best place to locate one's business. Many other factors contribute to a a CEO's preference.
I can assure you that SV executives flock to SV because of talent, in spite of California's tax system and business policies. We'd flock to Wyoming if Wyoming had more talent.