No they can sell their company to whoever they want. That doesn't mean however the CFIUS had to go along with allowing the new owners to carry on operations within the country. They could have instead opened up bidding to allow American companies to do it but chose not to.
Actually, they do have to go along with it unless credible evidence is presented to show the company has ties to terrorist organizations. The CONTRACT for port operations came with the company they purchased. You really think we're going to get cooperation from the UAE or any other country if we set a rule saying no "filty arabs" are allowed to have any business dealings with America? Yeah, that's a great way to gain cooperation.
Of course it does since the asset was transferred to the new company.
Unless you want the Government to write a law saying no Muslim can do business on US property?