The LS swap is the equivalent of gutting a classic computer or piece of stereo equipment and jamming in a Raspberry Pi. Occasionally it's an improvement, sometimes the original parts were too far gone, but a lot of the time it's just lazy vandalism.
I agree with you. In the case of this article the original parts were too far gone.
I do appreciate the physical aesthetics of older devices and would not vandalize functional and maintainable internals unless they caused extreme hardship.