No, it isn't. If there has ever been anyone to challenge 3:26, Kiprop is definitely the one to do it.
In this particular context, lets only use El G's performances up until he actually ran 3:26.
According to IAAF:
Prior to El G's WR 3:26.00 on 14 July, 1998, El G had run under 3:30 a total of 8 times, along with 2 mile races worthy of sub 3:30, for a total of 10 sub 3:30 performances:
1996 - 3:29(2)
1997 - 3:29(3), 3:28(2), Mile - 3:44(1), 3:45(1)
1998(before 3:26 WR) - 3:29(1)
So up until El G ran 3:26.00, he had basically run under 3:30 10 times.
However Kiprop is not a time trialer. He prefers to just race and rarely goes for fast times. And yet despite this, he has run under 3:30 3 times so far! Had he been going for fast times these past few years, don't doubt for a second he would have racked up a slew of 3:29s.
Also, here's an interesting stat,
Heading into his WR race, El G's 1500m PB was only 3:28.91 from the year before.
At the same age(23), Kiprop ran a 1500m PB of 3:28.88!!!
So age-wise, Kiprop and El G seem to be neck and neck up until age 23.
El G is rumored to have run a 1:42 in practice once. Assuming it is true, we must remember that Kiprop ran 1:43.15 at the age of 22 when he was still just a 3:30 man, remember that. So we have a confirmed 1:43.15, vs. a rumored 1:42.7. Hmmm....
Also Kiprop was a world junior cross country champion, beating some very good runners who today run long distance. He's plenty strong.
Weaker? What are you talking about? Aside from Lagat and Ngeny, who did El G have to contend with? Cacho and Morceli were on their way out, Baala could never put a season together aside from 2003, and everyone else would get thoroughly wooped by El G.
In the 2000 1500m final, they only closed the last lap in 54 seconds off a 3:32 race, and there were only 2 guys anywhere near El G! Everyone was dusted! Compare that to the 2012 1500m final, where a bunch of guys closed a 3:35ish race in 53 or under! This era of 1500m running is far stronger than you give credit.
It's not ridiculous at all to put El G and Kiprop in the same league for the reasons highlighted above.