The author might be a moron, but this is not evidence of it.
The 44.1 kHz sampling frequency is theoretically able to ensure a 20 kHz pass-band for audio signals.
But this does not mean that this is true for an actual recording.
A 44.1 kHz ADC cannot be used without being preceded by an analog low-pass filter.
An analog low-pass filter that blocks signals over 22 kHz and passes those under 20 kHz has always been and it would be even today very expensive.
That is why many early CD recordings may have used worse anti-aliasing filters, which could have reduced the pass-band to significantly less than 20 kHz, possibly also introducing audible artifacts due to a non-flat frequency characteristic at the high end of their pass-band.
Because of the great difficulty of making digital recordings when using a 44.1 kHz sampling frequency, as soon as faster ADCs became available, the standard method has become to use at least a double sampling frequency or even better a quadruple sampling frequency, and then use digital filtering and decimation for creating the CD audio.
However this became possible only many years later after the introduction of CDs.
Comments
The author might be a moron, but this is not evidence of it.
The 44.1 kHz sampling frequency is theoretically able to ensure a 20 kHz pass-band for audio signals.
But this does not mean that this is true for an actual recording.
A 44.1 kHz ADC cannot be used without being preceded by an analog low-pass filter.
An analog low-pass filter that blocks signals over 22 kHz and passes those under 20 kHz has always been and it would be even today very expensive.
That is why many early CD recordings may have used worse anti-aliasing filters, which could have reduced the pass-band to significantly less than 20 kHz, possibly also introducing audible artifacts due to a non-flat frequency characteristic at the high end of their pass-band.
Because of the great difficulty of making digital recordings when using a 44.1 kHz sampling frequency, as soon as faster ADCs became available, the standard method has become to use at least a double sampling frequency or even better a quadruple sampling frequency, and then use digital filtering and decimation for creating the CD audio.
However this became possible only many years later after the introduction of CDs.
This is exactly what I mean by cheap digital production tools; but it's been possible to do it right since well before cds.