From Stamp4 to Irish Citizen spouse

Asking on behalf of a friend. His wife was granted Stamp4 on humanitarian in 2015. He himself was granted Stamp4 in 2016 based on his wife and kids. They're both Non EU and married in 2016.

His wife recently got Irish citizenship in February 2022 and got her Irish passport.

He himself applied for Irish citizenship in 2021 and awaiting a decision.

He wish to change his status to spouse of Irish citizen. Does that make any sense? To be honest i don't see any advantage to his current status and since he's applied for citizenship and waiting for a decision any moment from now, doesn't make sense changing status and of what advantage? Nothing to gain from changing from normal stamp 4 to spouse of Irish citizen. Even if he change it, he can't exercise free movement like EUFAM so what's the point?

What do you think guys?

Spouses of Irish nationals can apply for naturalisation after 3 years of marriage and the stamp is free of charge.

If his stamp is still valid for a while, there is no reason to change it now. Besides I don't think INIS will allow him to change it when his current stamp 4 is still valid.