There have been many attempts over the many years that Baptists have existed to allow women to be the pastor of local congregations. To the best of my knowledge there has never been a doctrinal declaration given by a presiding president of any of the Baptist denominations that has excommunicated even one church because it had by its own will elected a woman as its pastor.
I have known several formerly SBC congregations that disavowed the denomination and become independents.
I have also known of two churches that, while aligned with the SBC, were excommunicated because they failed to remain biblical churches, but not over the issue of Women pastors. One of them openly practiced Wicca! And the second was involved in sexual immorality! Both were relatively small congregations that could easily be "swept up" into non-biblical practices.
Yes the SBC Denomination does have the power to say whether or not a church can become, and or remain SBC, but so does the local congregation have the power to disavow the denomination.
Unlike the Roman, the Wesleyan, and other denominations, the Baptist denominations do not own the real-estate of the local church nor does it have a say as to how it is used, but it does establish the standard for becoming and remaining SBC. This is kind of like becoming "a Christian", there is a standard established for the conduct of the one who would be "Christian", but the one can behave as one chooses. If the behavior does not meet the standard, then one is not looked upon as being "Christian". Churches that do not meet the SBC standard cannot be SBC.