When did LEGO stop using perforated plastic bags and switched to simple ones?
AFAIK TLG still uses these bags, and they are not unique to the 90ies. They are used for accessory bags, such as the one in your picture, or other various accessories such as these that came in the 2013 Friends Advent Calendar:

https://store.bricklink.com/v2/catalog/catalogitem.page?S=41016-11