Apart from that, if they are beginners, they should not be too selfish to buy aggressively because they need to strengthen their mentality when the price of Bitcoin changes suddenly. Because beginners often panic when prices fall because they are not experienced enough to deal with situations when prices fall drastically. For that reason, I agree with all the points which deserve to be a priority for us in accumulating Bitcoin for long-term investment.
I doubt that the justification for being aggressive has to do with whether someone is a beginner or not, and maybe the beginner has to be more careful about his level of aggressiveness, and since presumptively he would be in the earlier stages of learning about his investment, but as the person gets more and more systems in place and learns about his investment (and his cashflow situation) he thereby would be in a better position to increase his aggressiveness level.
Of course, for beginners, this will not prevent them from acting aggressively because if they have a lot of money, of course they will not be influenced by their decision to buy aggressively at the start of their investment. However, those who have not too big finances will definitely think about it if they act aggressively in the initial purchase. Indeed, arranging finances is a priority for beginners because they are still new and need learning to strengthen their mentality in Bitcoin investment.
I agree with you that the main point in taking aggressive action is not only carried out by beginners but also by old investors. So that they really think about the decision they make if their purchase is right at the lowest price point to trigger their enthusiasm to continue buying at the next stage. Even though this category is an investment for the long term, it is necessary to find a cheaper price if you want to do it aggressively.