The issue is that the taxes are redistributed as dividends evenly among the corporation members. Because of this in corporations with many players the governors have no control over the taxpayers’ money, which is a problem for funding the upkeep of POPI and COGC. The one player governor corp is a workaround for it and the only way for the governor to get all the taxes in his wallet.
This issue has been already raised on the forum :
I really hope that the devs will fix this issue when they overhaul the politics system.