The SPLC is a powerful left wing propaganda organization ironically dedicated to killing unborn Black babies among other things. Hate is a powerful weapon and that's why a Sanders democrat madman tried to murder an entire conservative republican baseball team. It's unclear if James Hodgkinson communicated with democrat politicians during the month he planned to kill conservative republicans but the liberal media dropped the story like a hot potato.
SPLC is a very valuable organization that watches and identifies hateful groups. Naturally, the people who support those groups do not like the SPLC. Unfortunately, the groups they support pretty much suck, so the only option they have to ostensibly 'elevate' these groups to normalcy is to drag down the SLPC and anyone else who criticizes their pet hate groups. This is not unlike religious people trying to put their faith-y ideas on the same level as evidence-based thought by trying to drag science and scientists down into the murk where their faith-y ideas reside.