Your right none of those scripture referred to having more than one spouse wrong. Not even close,but that is how the WT writes their articles. They show a scripture on fornication(single) with a husband then jump to polygamy as wrong! Whereas the scripture had nothing to do with multiple wives but an act out side the marriage bed, such as a husband having an afair with a none married person caught in the act of fornication.
And that not the only subject they messed up!
But Jesus did speak about how it was in the beginning a man leaves his parents a clings to his " wife" not wives. Goes on to explain about ztiff neck people. But the WT never brought that point out so it is jumping subject around. They do not expect you to question anything!
Deacons or elder with one wife compared to others who had multiple wives! :-)
I even think that Jesus spoke and fed crowds who had multiple wives. Five thousand men were fed but how many wives and their children. In those days they had big families.
Well anyhow I am not for polygamy but I wondered about that issue. If a man had five wives and committed fornication then five wives would have grounds for divorcement. Apparently it would not go well with his "wives." Scripture only has wife and not wives.
Still your point is reasonable.