Dear God in heaven above, Murdoc has gone and actually voiced the very thing I've been thinking all this while...
I'm just gonna be brutally honest and say I completely agree with all this... it's something I've seen quite a bit across many of the RPs I've been with in my time on here, even some of those that I myself have run are not innocent of this issue. Infact, it's quite hoenstly the biggest contributing factor to why I decided to stop trying to host things alltogether- the sheer effort and strain of having to always go so far out of the way to try to tailor things to have a path that is more straightforward or obvious just so that people wouldn't be scared to try things... that shit honestly got to be too much for me. Facotr in that I used to run multiple RPs at the same time too, and that stress was only going to get greater.
And I knew it would. And I knew I couldn't deal with it anymore, let alone if it continued... but I was too afraid to speak up or say something because I figured I'd have fangs at my throat in no time with the amount of potential backlash I thought could've happened... and I wasn't really in the right state of mind to deal with that either. So I took the lower road.
I didn't speak out. I just went and retired.
As for the actual cause and solution: I feel it is most likely something akin to what Ark has suggested- people may come in with the misconception that thinking abit outside the box or trying things that are not considered normal- ie taking their own initiative, might result in consequences that they feel are so utterly severe, such as a public rebuke or mod action, that they feel it is not worth the perceived risk of initiative... Basically, a combination of a lack of confidence, and a fear of the consequences that misstepping carries.
However, I also think that in these situations, there is a bit of issue on the side of the hosts as well- for enabling this type of misconception to continue throughout the interaction (And yes, I myself will raise my hand up high and admit that in hindsight, I'm just as guilty of enabling this as anyone else). In a way, by bending to the statement "I literally have nothing I can do" and changing things to give that player something explicitly designed for them, instead of just leaving the situation open ended like it was, and instead of altering it, trying to help the player figure out that they can infact do something, they simply didn't consider it themselves, we as host, in a way, only help to reinforce this apparent stigma against taking the first initiative.
And then there is the issue of overall communication. In many RPs, the rules as to what one is explicitly allowed to do in the story- I mean the freaking case law by which you can even operate, not just standard, typical rules like "No Godmodding, No Sues, Etc.". In alot of cases, the rules are not clear in telling how creative one can get, and what is generally allowed in terms of a response.
My case in point for this- My own Swansong: Sins of Avalon.
Going into that RP, I thought I had made it clear what I expected on people being creative, however, I was wrong and the guidelines I had set forth for the types of tactics and degree of creative thinking that would be tolerated and encouraged were never explicitly expressed beforehand. Now, this is more the result of an honest mistake than an actual oversight- when I was scrambling to salvage whatever I could after Auroral Starfall was destroyed via Computer Glitch, I failed to remember to take the details about the creativity and tactics and impart them into the interest check and OOC of it's replacement, Sins of Avalon.
Now... what did this result in? Someone at some point told me they had nothing to do. Now, that whole situation with me having to explain all the various tactics I myself could come up with off the top of my own head that was entirely possible and acceptable with the current moveset and species of pokemon they were using, could've been avoided entirely if I had just remembered that I never told anyone just what was the limit of things. I simply went in partially assuming they already knew, and that is where my personal sin lies, and where the sin of other hosts often lies aswell- Complacency, and Assumption.
Of course, I immediately rectified this issue when it arose by making sure that people knew what the limit was, but still... the fact that this basic miscommunication between a host and his players was allowed to transpire in the first place is entirely unacceptable in my eyes, regardless of what the cause of it happened to be.
That's all I have to say on the matter for now. quite honestly, I've spoken my piece and then-some.
TLDR; There are no fingers that can be pointed here; Everyone, hosts and players alike, are to blame at the end of the day. Therefore, the only way this will be resolved is if EVERYONE, HOSTS AND PLAYERS ALIKE, makes the effort to change the status quote that has been allowed to take form here.