New proposed theory is the same I asked in this network some years ago
No, you have no reason/right to claim co-authorship, or I believe any acknowledgement at all.
For those curious about the paper a preprint is here: https://arxiv.org/abs/2007.09560
I have skimmed through the paper and have some background in AI, but even ignoring the fact that the topic of the paper is different to what you wrote about, what you have linked to is no more then a random thought. Any contributions from you can be summed up in the following hypothesis:

Dreaming can be a significant advantage since it allows you to experience a virtual world, simulated situations and reactions, without taking any risks. In this way specimens who could dream were better prepared to face new situations and how to react.

This statement is very vague and doesn't actually specify anything. How are dreams simulating a virtual world? Why are dreams better than being able to run simulations while awake? How does the specimen decide upon which simulations to run? Possibly a good starting point to develop a more specific research question but not a research question by itself. The statement was also after you asking if anyone else had ever looked at this kind of idea.
Even if the author had read your statement and that had inspired him to start thinking more about the subject I don't believe there would be any ethical issues by not referencing you since the statement above feels lacking in substance to me (just like you wouldn't reference a handwaved/madeup science fact from some sci-fi book if it had inspired you to look into a topic).
Now considering the actual paper, and based on my skim of the paper a few months ago, the topic is actually different to what you suggested. The paper proposes that dreaming solves the problem of over-fitting. This occurs in reinforcement learning (AI) where the algorithm is trained on a data-set and can perform very well on classifying/responding to that data-set, but when input that it wasn't trained on comes in the algorithm does something stupid.
So instead of simulating the situations and reactions that the creature may run into, the paper suggests that dreams are the result of training yourself from your daily experiences, but with added random noise to the input training set (your daily observations). This means that you won't assume that everything will occur exactly the same as what you observed today, and that will be beneficial. Specifically it balances against the innumerable number of variables that you couldn't have been aware of which impacted your daily experience.