Plastic Backing was an adult diaper feature that used to include everything on the market. Years ago, when it was old school, everything was plastic backing. Now, only a few products, such as some sizes of the Tranquility Slimline Disposable Briefs, have a plastic backing. Abena and a few of the Mckesson products are plastic backings as well.
The reason why plastic backing was moved away from is because of personal preference. Products went to a cloth-like material and some people preferred it. There is a small difference in softer noise on the new cloth material. Note that plastic backing is hotter in the summertime and can cause skin irritation due to sweat and heat. If you are concerned, simply stick to standard cloth-like backing.
Some people still prefer their plastic backing for personal preference and seek it out. It has features they like such as its feel or fit, like when it comes to the popular Slim lines.
Plastic Backing is a personal preference that has been mainly, but not completely, handed off to people’s preference for cloth-like backing. However, plastic backing can still be found in a few key products for those people that prefer that material.
To conclude, there’s nothing wrong with plastic backing. It is a judgment call. It is a personal preference found on a few products. It has a more “plastic feel” that all diapers used to have, and is, simply, there if you prefer it.