Hashem is One, He is not All
Hakham Mordechai in the video linked here is explaining that ancient fundamental principles of Torah, such as the absolute oneness of Hashem, have been severely eroded or replaced since the Middle Ages.
The absolute oneness of Hashem precludes associating Him with any of the created entities.
Those influenced by radical "Kabbalistic" replacement theologies have replaced "Hashem is One" with "Hashem is All". Such theologies are very common in Chassidic groups like Chabad or Breslov.
For example, Chabad often cites Jeremiah 23:24: "Do I (Hashem) not fill heaven and Earth?". However, Chabad never seems to cite the commentary of Radak (one of the greatest Biblical commentators) on that verse: "...this is a metaphor because God does not have a body that fills space, rather God's providence is everywhere."
However, the claim that "Hashem is All" (i.e. the notion of “panentheism” in philosophy) is NOT an authentic Torah belief. The replacement theology of panentheism rejects the first verse in the Torah (Hashem created the Universe) and makes Torah observance based on Man's free will impossible. It erodes monotheism and promotes worship of created objects (such as a Chassidic rebbe) as intermediaries between Man and Hashem.