Daas,
5) Small shiurim (cf. Chazon Ish’ shiurim)”
A quick הערה, isn’t it the other way around, the Chazon Ish is relatively a new chumrah. The first one to mention anything about נתקטנו השיעורין is the נודע ביהודה בספרו צל”ח, until then each and every Jew followed the smaller shiur of the Shulchan Aruch.