Of course I will as always give him his due and say he's pretty good, and then be accused of trolling by understating things.
But you must understand that in every event he's good at, there are lot of all-time greats who definitely outshone him. All-time includes people who were slower than him who had great wins or impressive contributions to WR progression. Few would argue that he's well behind
1500: Ryun, Bayi, Nurmi, Coe, Cram, Ovett, Elliott, Coghlan, Keino, Aouita, Choge
5000: Viren, Ngugi, Zatopek, Kuts, Aouita, Yifter, Clarke, Rono, Choge, Hägg
10000: Viren, Zatopek, Kuts, Yifter, Kipkoech, Rono, Zatopek, Tergat
besides the standard mentions like KB, Geb, Komen, Lagat, El G and Kiprop.
When you start talking great of all time you have to figure in 50 years when people look back he will blend in with all these people and his golds won't shine so bright, being in relatively dull and/or slow races. So for sure, he's among the pretty good of all time, even if he dopes. Certainly a competitor. But he's no Emil MF Zatopek.