Note that the license still says you
may... not Share Adapted Material
Insofar as your isolated part is Adapted Material of the original, it is forbidden to share. If your isolated part is not Adapted Material, then it is allowed to be shared. Looking at one of the final drafts of CC BY-ND 4.0 (which is not legally binding, but may help understand intent), we see the phrase
the Licensor hereby grants You a [...] license to [...] reproduce and Share the Licensed Material, in whole or in part, including for commercial purposes, provided You do not produce Adapted Material.
The intent of this late draft is obviously that partial reproductions are allowed, but only if they are themselves not Adapted Material.
So, is a verbatim except from a work Adapted Material, or not? The definition of Adapted Material isn't perfectly clear on this point:
Adapted Material means material subject to Copyright and Similar Rights that is derived from or based upon the Licensed Material and in which the Licensed Material is translated, altered, arranged, transformed, or otherwise modified in a manner requiring permission under the Copyright and Similar Rights held by the Licensor.
However, I don't think it really matters: if your isolated part is Adapted Material after all, then it would not have been allowed under version 3.0. If it is not Adapted Material, then it would have been allowed under version 3.0. In light of this, regardless of the correct way to understand extracted parts on an ND work, it seems that there are no practical differences between 3.0 and 4.0 on this point, unless these is some subtle change in how 3.0 and 4.0 define adapted works.
The legal mechanics of this would probably be that the right to prepare derivative works and the right to reproduce the work verbatim are separate rights. In some jurisdictions, in some circumstances, reproducing an excerpt doesn't satisfy the legal definition of a derivative work, and so the right to prepare a derivative isn't needed; instead, only the right to reproduce the work is in play, which CC BY-ND does grant.