I believe even other Marxist-Leninists banned Lemmy devs from their own subreddits for posting neo-Nazi and LaRouche propaganda since the LaRouche movement has a history of being hostile towards MLs under "Operation Mop Up":
LaRouche began to become more strident in his attacks on perceived foes, said ex-associates and experts on the group. At his urging, many members learned karate and street-fighting techniques, they said.
In April 1973, LaRouche ordered members to attack members of the Communist Party (CPUSA) and others in a plan called "Operation Mop-up," according to ex-members and published reports.
The group's newspaper, New Solidarity, reported then that "the NCLC has launched 'Operation Mop-up,' which will bury the Nixon-allied Communist Party in six to eight weeks." The article said the group would enter Communist meetings to accomplish this. "We destroy the CP," it went on, "because it is an absolutely necessary step to ensure that the working class in the USA and Western Europe is prepared with competent leadership . . . ."
In the following months, there were about 40 fights at gatherings of Communists and others, according to former associates of LaRouche and published reports. Many people were injured, and some LaRouche supporters were arrested, but there apparently were no convictions.
"Mobile squads of helmeted, club-wielding goons invaded bookstores and offices of the CPUSA, Socialist Workers Party and Peking-line groups, attacking their members there and on the street," said the study by journalist Rees.
Former members said some attacks were in retaliation for assaults by Communists, and others were unprovoked. LaRouche said in an interview that his supporters fought only when attacked.
So, it' s not even "tankies being tankies". More of "we need to keep LaRouchies out to keep our organizations safe from being infiltrated by known snitches, fed/fascist collaborators and informants." Many MLs in organizing spaces are very pro-active in keeping LaRouchies out. Huge security concerns for everyone.
Apologies for the long comment trying to explain it's not really ideological "tankies versus anarkiddies" but rather a genuine safety concern.