Is Atenism a cult?

No. To elaborate on this answer, we should spell out what the term "cult" actually means. The word cult has two meanings:

The word is an abbreviation of the word "culture" and means the beliefs of a community of like minded individuals. By this standard, every religion is a community of like minded individual who believe the same things and would, by this definition, describe them as a "cult".

The word is a derogatory term used to describe disreputable and dangerous religious groups that use manipulation and intimidation to trick individuals into joining them. In some instance, these groups do not allow their members to contact family and some have ended in fatal consequences.

If, what is meant in the question, was the first definition, then the answer would have been "Yes" since all world religions would fit in this category. If what is meant is the second definition, then the answer is an emphatically and unequivocal "NO". Orthodox Atenism is a world religion that only has the welfare of its fellow brothers and sisters in mind. It does not use manipulation, intimidation or trickery to reach seekers, nor does it have any intention for taking advantage of these persons by trying to acquire their money. (There are tithes but these are part of the faith and individuals who research the faith are never committed to give anything they do not wish to or what they simply cannot afford.) Our faith would encourage its members to stay in close ties with their loved ones and would never encourage them to disassociate with family and friends, and as far as the final part of the definition that is a horrific concept and one that Atenists have no understanding or association with.

Atenism is about "Loving God and doing No Harm" the very definition of these destructive cults is in opposition to the principles of Atenism because all they seem to cause is harm, to the seeker or to their families and friends.