Linksys E3000 subtarget selection

I came across a Linksys E3000 and wanted to use it as a DNS server and Wireguard gateway for my parent's network (no AP duties for this thing). OpenWRT has supported the WRT610Nv1/v2, from which the E3000 is based, for quite a few years, but both models are placed under the brcm47xx/generic subtarget. That subtarget uses packages from the super generic mipsel_mips32 architecture. This makes sense for the WRT610Nv1, which contains Broadcom's custom MIPS32 SoC, the BCM4705 (

However, both the WRT610v2 and E3000 are also under the generic subtarget, despite having a standard MIPS 74k core in the BCM4718 SoC ( These devices could be taking advantage of the more appropriate mipsel_74kc package architecture by being placed in the existing brcm47xx/mips74k subtarget.

The OpenWRT hardware page for BCM47xx explicitly states that these two devices are the exception to the mips74k subtarget and are thus in the generic subtarget. Why is that? I could just flash and forget it, but I'm more curious than anything and after searching for hours I can't find anything on it.