My points are (1) Yes, Britain DID fight to eradicate slave traders from shipping lanes, (2) we did not fight an internal war over the issue because there was a widespread consensus that slavery was immoral and the focus of the debate was over the impact that freeing a large slave population would have on society, and (3) yes, slavery does happen but it is illegal in countries where it is practised with Saudi Arabia the last country to ban it.
Lots of stuff illegal happens every day without a word from those condemning something that happened elsewhere 100’s of years ago