I don't think that can accurately restore the details that have been created by subpixel-AA font rendering.
But if you have source/subsampled/interpolated comparisons that show 99% identical results i would be interested to see them.
Of course all that is useless if you don't have control over the output device. Just having the ability to record 4:4:4 makes the issue go away as long as the target can display it, no matter what interpolation they use.
50% solution: bicubic or bilinear. 90% solution: EEDI3. (kinda slow) 99% solution: use the full resolution Y plane for edge-direction.
I don't think that can accurately restore the details that have been created by subpixel-AA font rendering.
But if you have source/subsampled/interpolated comparisons that show 99% identical results i would be interested to see them.
Of course all that is useless if you don't have control over the output device. Just having the ability to record 4:4:4 makes the issue go away as long as the target can display it, no matter what interpolation they use.