When people state hype you have to fully understand the hype before your posts it.
He killed himself 5 years ago [
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, prior to the 3rd great war. Meaning Kakashi was roughly 8 when his dad died.
From this we can estimate the sannins age at the time of Sakumo's hype. Kakashi is now 30 and the sannins are 54, so there is 24 age year gap between kakashi and the sannins. Meaning if the sannins are 24 kakashi is 0. In that case if Kakashi is 8, the sannins were 32 roughly at the time of Sakumo's death.
We don not have a clue when the sannin's were in the prime, but you have to note that, the sannins have gained a further 54-32 = 22 years ahead of Sakumo in terms of strength and battle experience.
In other words you cannot compare the sannins of the past to the sannins of the present. The sannins of the past is whom this hype relates to and NOT the sannins of the present.
Anyway im sure he was something special going by Chiyo's reaction when she saw Kakashi however i do not believe his power still rivals the current sannins. Id say he was Low kage