I would say yes. Hiruzen knows all the jutsu in konoha. However dont think AT ALL that Hiruzen, can use/perform, all the jutsu in konoha. He would need to be able to use all 5 elements(something nobody known has been able to do before) and have ALL the kkg in konoha(something oro is still far away from)
He simply knows all the jutsu, and what they do, and perhaps how they work as well. AGAIN I dont think for a moment he can PERFORM ALL THE JUTSU IN KONOHA.
He was known as the professor. Professors are very knowledgeable about what they study. As Hiruzen studied the leafs jutsu, it would make sense he would know all of them.(again, know them...not be able to use them)
There are no feats or anything that interfere with this logic.