What kind of lenses with a “slightly different diffraction behaviour” were used in “large format photography in the 1980s”?

Referring to an interview with a lens expert (Krolop&Gerst Objektivreihe 17/32), discussing diffraction limits.

“Es gibt ein paar Spezialobjektive die haben ein bisschen anderes Beugungsverhalten, aber da möcht ich echt nicht drauf eingehen, also dass ist Grossformatfotografie aus den achtziger Jahren”

“There are a few special lenses which have a slightly different diffraction behaviour, but I do not want to go further into this, since that is specific to large format photography from the 1980s.”

What is the expert referring to here?