The difference is that Microsoft released consoles with very similar purposes and names in the same generation.
Labelling the Switch as a new version of the Wii doesn't make much sense because it occupies a different niche, comparable to PlayStation/2/3/4/5 vs the PlayStation Portable.
PlayStation's addition of "Pro" in it's own naming scheme clearly distinguishes the more powerful console. Delaying the release of the pro model until later in the generation's lifecycle also helps reduce friction.
Labelling the Switch as a new version of the Wii doesn't make much sense because it occupies a different niche, comparable to PlayStation/2/3/4/5 vs the PlayStation Portable.
PlayStation's addition of "Pro" in it's own naming scheme clearly distinguishes the more powerful console. Delaying the release of the pro model until later in the generation's lifecycle also helps reduce friction.