Just for fun, from the first example:
* Toilet paper -> bathroom tissue --- sure, a softening of the language.
* Sneakers -> running shoes --- not a softening; sneakers aren't the same as running shoes, and "sneaker" was a regionalism (it's "gym shoe" where I grew up).
* False teeth -> dental appliance --- a softening, though a welcome one in this case.
* Medicine -> medication --- a softening (a nominalization of a denominalization, at that!). Down with medication!
* Information -> directory assistance --- arguably, this is a hardening, since directory assistance carries more meaning and carries it more precisely.
* The dump -> landfill --- a dump is not a landfill. The word changed because we stopped building open-air unchecked dumps and started building regulated landfills with groundwater protection and load checking.
* Car crash -> automobile accident --- a softening, though he's getting some mileage out of switching "car" to "automobile" (I can hear his voice very clearly in my head dancing over the syllables in "auto-mo-beeel") and the real language is "car accident".
* Partly cloudy -> partly sunny --- I think he made this up.
* Motels -> motor lodges --- This is a softening, but it didn't take; look up "Econo Lodge", and it's a motel, not a motor lodge (Choice Hotels will call it a "hotel" though).
* House trailer -> mobile home --- A softening; by the end of his life, he'd have been able to use "manufactured home" here instead to drive the point further home.
* Used car -> previously owned transportation --- A softening, a good example of one, but again notice that he's smuggled the word "transportation" in to make it more zippy. "Certified pre-owned" is a much funnier term (imagine the shape his eyeballs would take while noting the "certified" here). I miss Carlin!
* Room service -> guest room dining --- A softening, and also: why?
* Constipation -> occasional irregularity --- A softening, if you will, and again he's made it artificially softer with the "occasional".