Mutah is pre-Islamic, and the actual verses seem to me to be about the need to pay in full if you have contracted a woman for her sexual services. So it was more about getting men to behave better in the world as it actually was back then. Not recommending prostitution, but acknowledging it existed and stipulating that you could not bilk a woman. I suppose it was an older equivalent of the arguments in favour of legalising brothels to protect those who provided the services.
It is a shia concept, and though there is a parallel in sunni, it doesn't seem to carry the same weight (IYSWIM, that's not quite the right word, but I can't think of better right now). So I don't see it as a feature of Islam per se.
Issues such as age of consent also are not necessarily linked to religion, and forcing or coercing a woman into marriage (permanent or temporartyh are definitely not. Yes, in RL abuses happen, and clerics do speak on this.
Perhaps the way forwards is to make sure that people do hear what those clerics are saying. Because people are standing up for them, but if you only read the western media then you probably woukdn't see much about these issues