Anzac events are going ahead as normal in most places. QLD, WA and ACT are as normal, and I understand NSW events might be restricted to 500, so suburban and regional services will be fine, but the main street march will be restricted. Victorian government has committed to try and make it as normal as possible but being 7 weeks away its probably to early for them to be fully committed. Tasmania has called off the public commemorations in Hobart, but there will still be a restricted dawn service. i;m not sure about the rest of the state. is only state i'm aware of that has called it off again in 2021. Overseas ones of course aren't going ahead. Don't know about SA/NT.
If the RSL or whoever wanted to make an application for an exemption somewhere where the an event was being restricted a few days before Anzac day they are free to do so, but with the amount of organising that goes into Anzac day services and the number of elderly people involved, that is unlikely.
I think people really underestimate how much goes into events - hence why the actual Mardi Gras organisers thought out of the box and went for the official event they are having at the SCG.