I'm also not impressed with SegWit, but I'm not aware of the said bug, do you have any sources?

Extraordinary long confirmation time and high fees recently has been due to hashpower "defecting" to mine on the Bitcoin Cash chain - possibly combined with a spam attack. Things are already back to normal now, over the next few days there will be low fees and fast confirmations in the Bitcoin network, and this is not at all related to SegWit.