All previous installs to version 9 had a folder structure like this:

    /Data
    /Databases
    /Website

Now in version 9.x the /Data directory is nested inside the /Website root. SIF default logic even has code that places it there.

    "Site.DataFolder": "[joinpath(variable('Site.PhysicalPath'), 'App_Data')]"

Just curious if this was intentional? No performance worries about indexes due to Solr files in separate directory? To support Azure deployments?