It is true that we have had, and continue to have, many successes in kiruv. If kiruv rechokim is perceived as being “no longer successful,” it might be because of two challenges.
The first is demographic. The population of non-Orthodox Jews in the United States is aging and becoming fewer in number. With an intermarriage rate of over 50%, and assuming that roughly 50% of those intermarriages are between a Jewish father and a non-Jewish mother, a large portion of Americans who even identify as Jews are not halachically Jewish. Some kiruv professionals have told me that they need to gently and tactfully learn whether the person they are speaking to is actually Jewish, no matter how sincere the person seems, or how “Jewish-sounding” the name is. I know of several cases where individuals engaged with a kiruv organization, only to learn that they were not Jewish, and to have their “kiruv” process turn into one of geirus instead.
The other challenge is cultural. Americans, particularly those who went to public school and especially those who went to universities, are taught that all people are equal, that all religions are the same, that there are no absolute truths, and that anyone’s beliefs are just as valid as anyone else’s. If you say that 2+2=5, then 2+2=5, because you said so, and therefore it must be true for you. Add to the mix the belief that universalism is good, that tribalism is bad, and that Jewish tribalism is the worst of all. Modern liberal thought is diametrically opposed to Torah concepts such as schar v’onesh, am nivchar, etc., but this the mindset that the kiruv professional must confront.
All that said, we must give tremendous hakaras hatov to the kiruv professionals who make great personal sacrifices and persist with incredible dedication to draw our fellow Jews closer to Torah and mitzvos.