Why do mainlanders change their nationality when investing in listed companies in Hong Kong?

People with China nationality can really invest in Hong Kong listed companies, give up their China nationality and change their foreign nationality. The main purpose is to transform themselves and the company from domestic capital to foreign capital, and invest in enterprises, so that they can enjoy preferential tax treatment for foreign capital in the mainland. At the same time, in order to facilitate listing in Hong Kong, domestic capital and companies need to go through the mainland authorities before listing in Hong Kong. Please understand. ..