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.
I understand your point sir, the aggressive situation when dealing with bitcoin investment for beginners is not advisable and if focusing on buying only and forgetting to learn at that early stage the person might end up with another story, sometimes newbies focus more on buying aggressively cause of the profit and wanting to reach their target, although it's best for everyone to have a target when investing but not without the investment knowledge, for example when I bought my first coin I started with just a little amount and as times goes each week I keep increasing gradually.
In terms of learning about investment this forum is the best place to learn about bitcoin and investing just like I have benefited more from other members in the forum concerning investing.