NSX 4.2.3.X , 4.2.X , 9.0.X
In the newer versions of NSX(4.2.3.X , 4.2.X , 9.0.X ), the backup config is modified on the product level to accommodate a shorter directory path and newer directories(nsx-bkp, nsx-inv) with shorter name is configured to be created on the event of a backup.
This is not an issue and if the backup task completes without error, consider the backup is taken successfully.