Does the startup founder still have enough shares to call the shots? Board seats in a typical US corp are filled by shareholder votes. If this isn't addressed

Does the startup founder still have enough shares to call the shots? Board seats in a typical US corp are filled by shareholder votes. If this isn't addressed by state law or the corporate governance docs then absent something weird if the resigner didn't voluntarily relieve the board of his presence an emergency shareholder meeting can do it for him. Of course IANYL