I am similarly dubious of the idea that TV consoles will be abandoned. Handhelds necessarily require low power. Even the steam deck is considered too heavy for many users, and it struggles to run present generation games at 800p.

Nintendo is in a special situation. They have a successful handheld line established in the Gameboy. Their games tend not to be realistic, instead going for more cartoon-ey or Anime style that can be done with low poly counts and lower resolution textures. Nintendo didn't abandon their home console so much as they merged with with their existing handheld console.