Without giving an opinion on any side: there is (and will continue to be) growing instability when inequalities (relationship, wealth, or otherwise) result in a large portion of the population disaffected. Historically the solution to this particular problem has been enforced monogamy + the risk of pregnancy. Clearly that is no longer an option in the West, as sexual attitudes have become more open and birth control is widely available. It remains to be seen what the end result will be this time around.
Personally I think that technology will try (and largely fail) to address this imbalance. Think of K's "girlfriend" in Blade Runner 2049. This seems to be the route we as a society are heading toward. A civilization of hyper-individuals that attempt to fulfill all social and human needs through market-based product solutions.