Eh, just because it has the pixels doesn't mean it has the resolution. Often 1080p content from high quality systems still looks more detailed than 4k content from smartphones, even fairly modern smartphones, as the pixels can only record detail that gets through the optics and isn't marred by noise. With phones having relatively low quality lenses (for the size of the pixels they must resolve) and smaller sensors, this can quickly become an issue. With that said, it is great to see 4k becoming standard for productions!