[the_daug]

Replacement theology leads those who have adopted it to believe that Israel is no longer God’s people and that the modern regathering of the Jews in their historical land is theologically meaningless.

Why does Satan care?

[Roman_War_Criminal]

Because it leads to Anti-Semitism and it’s a lie.
Who do you think lies and is the Father of lies?

Why does he doe it?

[imardmd1]

Why does Satan care?

Because "Replacement Theology" (and practice of it) lends that religious organization an excuse to nominate hieratic priests, a clergy class trained to lord it over a separate class of "lay" constituents conned into believing the cult's philosophy of being the only channel of communication with God.

Jehovah God truly hates this scheme, as an outworking of sin and death, the tool of lying Satan. Jesus admonition to the president of the synagoguing assembly at Pergamos in John's time was this:

Rev.2:14-16 (AV; bolding added for emphasis, superscript asterisk to notes)

  ¹⁴But I have a few things against thee, because thou hast there them that hold the doctrine of Balaam, who taught Balac to cast a stumblingblock before the children of Israel, to eat things sacrificed unto idols, and to commit fornication. 
¹⁵So hast thou also them that hold the doctrine of the Nicolaitans*, which thing I hate.
¹⁶  Repent; or else I will come unto thee quickly, and will fight against them with the sword of my mouth. 
-------------
* Note:
In NT Greek, Νικολαΐ́της, a combination of two words:

νικάω (nikaō, pronounced nik-ah'-oh)
A verb
From G3529; to subdue (literally or figuratively): - conquer, overcome, prevail, get the victory.

λαός (laos, pronounced lah-os')
A noun
Apparently a primary word; a people (in general; thus differing from G1218, which denotes one’s own populace): - people.

A coined term combining the two, a clergy class meant to overwhelm and subdue the class of non-priest constituents of a church known in that environment as "lay people."

This is Satan's way of perverting an assembly of professors of allegiance to the "Christ" as explained to them, by appointing the kind of officers equivalent to the Levitical priests of the Jewish Mosaic Covenant.

That form of religion was abolished, and the Mosaic Covenant abrogated, by Jesus' cross-fulfillment of God's righteous demands of a human based on Adam's sinful behavior. To reinstitute it by attempting to take the place of Jewry is to refute God's plan of reconciliation and salvation.

Y'all need to see that this arises from Satan's desire to be the god over humans, one by one; and displace The Triune Jehovah Elohim Who is a human's benefactor.

Figure this out for yourself, now. Do you need another intercessor with the Father other than His Son?