What's wrong with telling someone that something can already be done? If you say: "mIRC should be able to do X" and I say: "mIRC can do X, here's how: ...", why is that not a good response? Why would your response be "but I don't like that and still want X!"?
To me the problem lies in the fact that people are not asking for functionality, but rather they are asking for the same functionality in a different form. In other words, when you say, "mIRC needs <specific identifier here>" you're not asking for a solution to a problem, you're asking for your own solution to a problem with an existing solution.
This begs the question: why can't the existing solution work? Note that in many cases, the existing solution can be scripted.
The problem of IGNORING existing solutions is that we end up with a scripting language that has hundreds of solutions for the same problem. It's the known problem of software bloat. Bloat is NOT a good thing. We don't need more than one way to do things-- it just makes the language complex, the implementation large, maintenance much harder, and for little benefit.
Lastly I should point out that the "it can be scripted" solution in this case is EASY. It's so easy, in fact, that using "ON *:LOAD:" is actually fewer characters than using an "if ($isstarted)" check if you actually ran into that scenario. And, especially in this case, when the solution is already about *scripting*, telling somebody that it can be scripted seems perfectly apt to me. "I need a way to script X" -- "here is how you script X" ... what is the problem?