The lack of perceived evidence about endangerment is in the minds of SOME CPS people looking at some cases here in the UK. Lots of cases have not been taken to court because of these concerns, which is why the new lesser offence has been created. [In some cases, I suspect they would be right - it does depend on the evidence - the last thing you want is scrotes being found not guilty].
My comment about the CPS advising the court of the Court of appeal judgment related to the endangering offence, which remains and certainly allows jail sentences.
I can't agree with your last comment. If you compare it with assaults, then it makes sense to have various offences reflecting different seriousness of the circumstances. In the UK it goes something like: common assault, actual bodily harm, grievous bodily harm, attempt murder and so on. Which one is chosen depends on the evidence.
Horses for courses.......