I mostly agree, but the religious morality I know of isn't very nuanced, needs lots of interpretation to apply it to the present and is far behind secular morality in terms of equality and liberty. Except for a history lesson, which has its value, I do not agree that religion is still relevant to modern morality. If anything, it is holding us back.
I largely agree too, but where we disagree is interesting. Secular morality exceeded most religious morality some time back, and is now a hindrance to human progression. That is not the same as religion being irrelevant.
It is relevant for two reasons. One, which we have touched upon, is that they contain the history of much of modern morality. By analogy, the events and people that have shaped your personal morality are not just some things from your past that you can do without: they fundamentally shaped how you make moral decisions today. So too human history has shaped our morality today, and understanding this history helps us make sense of how we came to our current state and how best to proceed.
But perhaps more importantly, the vast majority of the world is religious and uses religion to make ethical decisions. It say religion is irrelevant to any moral discussion is to say the majority voice on Earth is irrelevant because a minority has exceeded such retrograde thought and knows better.
In my opinion such sentiments are partially responsible for the wave of populism sweeping through the Western world: many people are getting sick of being considered irrelevant. Instead of telling people they are irrelevant we need to find some way of engaging with them, as unpalatable as that may seem. This means learning to engage with religion as it seems many of the disenfranchised seem to be religious.