The Switch doesn't have access to any major streaming platform. This is true even 4 years after its release. Do you really believe that they will make a new Switch model with 4K to use it on stuff Nintendo has made very clear they give two shits about?
Streaming money is in expensive premium accounts with 4K HDR+ content and Switch can't offer that so streaming companies are avoiding Switch. These services will be available on a 4K capable Switch Pro.