if I recall my parochial lessons from the '60's, one of the vows taken during the 3? degrees of commitment was to take the habit (garb) as a clear sign of the faith.
“The fact that there is not a single “nun” donning anything resembling the traditional habit in the provided image should help explain why there are so many lapsed Catholics.”
To me it explains why there are no more nuns; one doesn’t have to take vows to engage in left-wing activism.
Remember these people when collections are taken for retired religious; their orders are often sitting on valuable real estate - they probably don’t need your money.