Buy infusions now?
My take on it is that the +5 AR Versatile Infusions will be different from the +1 AR infusions. I’m guessing you won’t be able to place the current ones into the infused slot.
The people who currently have an infused ring, will get a +5 Agony infusion already slotted in.
There’s nothing said about the versatile one for offensive/defensive/utility slot being removed.
The old infusions are not changing at all. A new slot is being added for infused items that will take a new agony resist only infusion.
Friendly reminder: You lose all infusions when you upgrade your items to the infused version. Do NOT spent 100+g on an infusion before you infuse it to the highest level.