Cult is a dangerous term to throw around and it obviously doesn't apply in the narrow sense to Musk's followers, but there are some aspects that give one pause.
Take a look at the following list from former FBI agent Joe Novarro [emphasis added]:
If you know of a cult leader who has many of these traits there is a high probability that they are hurting those around them emotionally, psychologically, physically, spiritually, or financially. And of course this does not take into account the hurt that their loved ones will also experience.
Here are the typical traits of the pathological cult leader (from Dangerous Personalities) you should watch for and which shout caution, get away, run, or avoid if possible:
He has a grandiose idea of who he is and what he can achieve is preoccupied with fantasies of unlimited success, power, or brilliance.
Demands blind unquestioned obedience.
Requires excessive admiration from followers and outsiders.
Has a sense of entitlement - expecting to be treated special at all times.
Is exploitative of others by asking for their money or that of relatives putting others at financial risk.
Is arrogant and haughty in his behavior or attitude.
Has an exaggerated sense of power (entitlement) that allows him to bend rules and break laws.
Takes sexual advantage of members of his sect or cult.
Sex is a requirement with adults and sub adults as part of a ritual or rite.
Is hypersensitive to how he is seen or perceived by others.
Publicly devalues others as being inferior, incapable, or not worthy.
Makes members confess their sins or faults publicly subjecting them to ridicule or humiliation while revealing exploitable weaknesses of the penitent.
Has ignored the needs of others, including: biological, physical, emotional, and financial needs.
Is frequently boastful of accomplishments.
Needs to be the center of attention and does things to distract others to insure that he or she is being noticed by arriving late, using exotic clothing, overdramatic speech, or by making theatrical entrances.
Has insisted in always having the best of anything (house, car, jewelry, clothes) even when others are relegated to lesser facilities, amenities, or clothing.
Doesn’t seem to listen well to needs of others, communication is usually one-way in the form of dictates.
Haughtiness, grandiosity, and the need to be controlling is part of his personality.
Behaves as though people are objects to be used, manipulated or exploited for personal gain.
When criticized he tends to lash out not just with anger but with rage.
Anyone who criticizes or questions him is called an “enemy.”
Refers to non-members or non-believers in him as “the enemy.”
Acts imperious at times, not wishing to know what others think or desire.
Believes himself to be omnipotent.
Has “magical” answers or solutions to problems.
Is superficially charming.
Habitually puts down others as inferior and only he is superior.
Has a certain coldness or aloofness about him that makes others worry about who this person really is and or whether they really know him.
Is deeply offended when there are perceived signs of boredom, being ignored or of being slighted.
Treats others with contempt and arrogance.
Is constantly assessing for those who are a threat or those who revere him.
The word “I” dominates his conversations.
He is oblivious to how often he references himself.
Hates to be embarrassed or fail publicly - when he does he acts out with rage.
Doesn’t seem to feel guilty for anything he has done wrong nor does he apologize for his actions.
Believes he possesses the answers and solutions to world problems.
Believes himself to be a deity or a chosen representative of a deity.
Rigid, unbending, or insensitive describes how this person thinks.
Tries to control others in what they do, read, view, or think.
Has isolated members of his sect from contact with family or outside world.
Monitors and or restricts contact with family or outsiders.
Works the least but demands the most.
Has stated that he is “destined for greatness” or that he will be “martyred.”
Seems to be highly dependent of tribute and adoration and will often fish for compliments.
Uses enforcers or sycophants to insure compliance from members or believers.
Sees self as “unstoppable” perhaps has even said so.
Conceals background or family which would disclose how plain or ordinary he is.
Doesn’t think there is anything wrong with himself – in fact sees himself as perfection or “blessed.”
Has taken away the freedom to leave, to travel, to pursue life, and liberty of followers.
Has isolated the group physically (moved to a remote area) so as to not be observed.