Dear Mr A Non, please contact me using a proper email address at mike @ oysterfares.com.
Multiple routes using different zone ranges is not new, but the high profile nature of the Elizabeth line does mean that some new cases in East London have become obvious. There has long been a case for a pink reader at Woolwich Arsenal so I doubt that anything will happen now.
As for pink readers in general, touching them is entirely optional so they could never be used to prove that a higher fare route had been taken. Most of them do prove that zone 1 has been avoided, but there are a few other uses too. In particular the one at Rayners Lane often proves that zones 1, 2 and sometimes 3 have been avoided. Also the one at Highbury and Islington can sometimes say that zone 3 has been avoided. Yes, really!