This reads to me as "why do we need cars when we have horses", portable mode doesn't feel very good compared to docked for some reason, maybe ergonomics?
From what I read in the past Dolphin on the Horizon can't be done. SM64 and Sunshine are emulated so Nintendo has the ability to emulate the games with the tools and resources. Which brings to the conclusion why don't we simply have a N64 online and a Gamecube Online the same way we have SNES/NES online.
Our devs don't have the capabilities/resources to make that happen so the best we have are Lakka/Linux/Android on Switch
This is a very informal video