Because Kiwi Farms hasn't been relevant since the Keffals drama and the only times people really talk about Kiwi Farms anymore is whenever people talk about ancient Internet drama from the 2000's and the 2010's that young people don't care about (because Kiwi Farms back in the day involved themselves a lot in old lolcow drama that people have to talk about them).
But these days? The last time Kiwi Farms was truly relevant was with Keffals and Kiwi Farms hasn't been the same since.
Probably the difference between 4chan and Kiwi Farms is that at least 4chan doesn't stay in the past and the 4channers are aware that they're degenerates and terrible people but Jersh wants to relive his glory days as he is becoming older and fatter and probably balder now (at least the 4channers are self-aware enough to see that as you get older you can't run like you used to).
Why do people still watch Mister Metokur? Because Jim never took the Internet that seriously. Jim knows that at the end of the day, people come and go online and so there is no reason to get that invested into stupid shit no one will care about years from now.
The Kiwis however do take the Internet seriously which is why even those in the Lolcow Community are starting to see Kiwi Farms as a joke now (especially after the OneyPlays fake news shitshow). Jersh and the Kiwis forgotten the number one unwritten rule of the Internet; which is don't take the Internet that seriously. A lot of people on the Internet are too employed and earn a paycheck to care about what Jersh and Kiwi Farms thinks anyway.