Thank you very much for the feedback. You have a different level of knowledge; I am still learning. The information in your comment is very valuable.

I just want to reflect on a thought experiment. What if we imagine that RC doesn't exist—what, then, would prevent a malicious actor from using software to create millions, billions, or even trillions of transactions (what could possibly limit that number)? In this case, the transaction queue would keep growing, and the waiting time for regular user transactions would also increase. If we imagine this playing out, with transaction processing times reaching, say, one week or even one month, wouldn't that essentially mean collapse?