Actually, the whole concubine thing was a Bad Idea in a lot of different ways, but certainly King Solomon was getting pressured to do it for many different reasons.
There’s a Great Courses about Mesopotamian history, that talks a lot about the shared diplomatic culture of Sumer and other Middle Eastern states, all the way through Babylon and such. In Sumer, kings’ daughters were trained to become queens and wives as a way for more important kings (their dads) to exert their will on less important kings (their husbands). They also constantly reported back to their dads in letters, sent by secure couriers.
In Egypt, on the other hand, a pharaoh almost always had his daughters and female relatives as queens and wives, while concubines were the children of commoners (even powerful commoners) or foreigners. So princesses from Sumer who moved to Egypt were still sending letters back, but they didn’t have power like they would have had at home. (There were a couple commoners who became queens for love or their dads being prime ministers, but never any foreigner queens.) Accepting foreign princesses as concubines was a sign of the pharaoh’s status, and was part of diplomacy with lesser states.
So Solomon and his people seemed to have thought they were Egyptians, when it came to foreign wives. His real wives were from Israel or even from his own tribe, and the queen mother was the really important lady of the palace. But the foreign princesses thought they were from bigger and more powerful states, and should rule Solomon. And sometimes they did.
Jezebel, OTOH, is a great example of a Middle Eastern princess wife taking control of her minor king husband.
And since most Middle Eastern monarchies believed in having the king and queen Do Magic Stuff as representatives of the lead god and his wife, and having all the sons, and the daughters who didn’t marry, become priests and priestesses of various gods and goddesses, as well as filling government offices…
Yeah, not good to have foreign pagan royalty around the house of a monotheist king.