Were the War in Heaven Era Eldar stronger psykers than the Emperor?

How does the Big E compare to the strongest pyskers that were in the War of Heaven? Iirc, he did defeat the void dragon, a c'tan shard, albeit with a lot of effort.

Eldar are psychically much weaker now due to Slaanesh, but even with that being the case someone like Eldrad can still stop time and go toe to toe with Magnus iirc.