I'm not too sure about that. Lakka, since it runs outside of OFW, should be able to avoid bans. After all, since Lakka runs entirely from RAM/SD card (and doesn't touch the NAND, or any Horizon code), It's very unlikely that there's any way for Nintendo to detect it. I know some people will say "Nintendo could look on the SD card for Lakka's files, and ban your console if they're found." While true, it'd be very easy to thwart this, by simply removing thr SD card before you boot into OFW. Theoretically, they could do a RAM search at startup, to see if anything non-Horizon shows up, but due to RAM decay (what's stored in RAM decays the longer the RAM is without power), that method would be unreliable (and easily defeated, if Lakka had a "shutdown" feature that involved clearing the RAM).
I realise that Lakka lacks on-board audio support, but I'm more likely to use my bluetooth headphones anyway, so that doesn't bother me. The biggest thing holding Lakka back, in my opinion, is there's no "sleep" or "low-power" mode. Or, as I understand it, a shutdown/power-off function (I haven't used Lakka, though I intend to, so I could be wrong).
Yes, being able to load RetroArch within OFW is nice. But, for those who are paranoid about being banned, I think Lakka has a very strong position. Mouser X over and out.