Here's a fact rarely discussed outside of super nerdy gaming circles. The guts of your video game console actually matter. Once upon a time games were designed to run the same on every console and, in some cases (like the massive multiplayer first person shooter Destiny 2), games are still designed that way. But most games have what is called a "dynamic resolution" with the resolution shifting on a spectrum from as 720p to 4K depending on the scene.
Thus the more powerful the console the higher and more consistent the resolution of the game you are playing will be. Want something close to consistent 4K without spending a grand on a PC gaming rig? You need a powerful console.