Ben Scott
Veteran
The producers asking for specific lenses are likely those engaged in productions for channels who are charging a premium for pixels no body can see.
Or they like the look/rendition/skintones of a certain type of lens. Or they want continuity between shows/series. Or the Director specifically wants the nice organic tones of K35s or Superspeeds or the flaring characteristics of Lomo sphericals or Super Baltars or the 'Cooke Look'.