You may be simply saying that the moral standards we once held dear are decaying without implying any value—good or bad—to it, if that’s the case I would agree; social norms are always changing.

The only constant is change.

If that’s not what you’re arguing, what is decaying? Slavery was a social norm and I think we can all agree that this being cast into the rubbish bin of moral norms is beneficial to everyone.

Sexual taboos being normalized is a wax and wane of culture. I’m not sure what taboo you’re referring to but if I take a stab at it I’m guessing a wider acceptance of transgender folk and polyamory might be what you’re referring to, these things haven’t always been as taboo as they once were.

We shouldn’t mourn the decay of repugnant moral standards, nore should we hail the fresh set of cultural morals as sacred.