I am utterly baffled why so many would engage in the raw evil of encouraging new writers.
There are four very, very good reasons why one should never encourage new writers:-
1. Encouraging new writers is the equivalent of trying to popularise taking up Russian Roulette as a sport. It is going to be an utter beating out there. 250,000 screenplays arrive each year in Tinseltown, of which just 600 are made and about 200 provide a sustainable living.
2. In an already crowed, packed field, encouraging someone talentless undermines hard working talented people, struggling to make ends meet.
3. In encouraging talentless people to take up writing, one is, de facto, encouraging them NOT to do what they are actually talented at, deriving them of a living and the world of whatever they are actually taleted at.
4. People generally work hard for their money. It is disgusting to see audiences waste their hard earned dough of watching utter crap produced from someone's bad screenplay.
You've gotten a lot of responses (of which I'm not going to read all of them before commenting) so you've obviously touched on something here.
What I will say is:
1) Yes, the odds of success are low. But if someone has a passion for it, who am I to stop them? And if they truly do have a passion for it, they sometimes can and will get better, and if I can offer advice or insights to help someone follow their dream, then why wouldn't I? the problem is, most aspiring screenwriters aren't really in it because they love the craft, but simply because they want to make a sack full of money by slapping together a script in a few months. I don't encourage that at all. If they're not serious about it, they'll usually drop out on their own.
2) Yes, there are some truly passionate and yet, talentless individuals out there. But there are also some truly passionate and talented individuals out there as well. I don't judge between the two as I don't read their material. I just like to offer advice if I can. But yes, I also remind all of them that the road is long, the odds are slim and without a lot of hard work and dedication, they have very little chance of success. After that, it's on them. Ultimately the talented, hardworking screenwriters will rise to the top. You can't cull the field just because it would make things easier for those deemed "talented". And who is it that determined that you (or I or anyone) are part of the talented crowd that should be encouraged and not the untalented group that should be ostracized?
3) Again, who determines what someone can or should be doing with their life? You might be exceptionally talented as a bricklayer and writer. Since you haven't made it as a screenwriter yet, are you depriving the world as a bricklayer? If someone wants to play violin but aren't very good at it yet (but practicing to get better), are they doing the world a disservice if they know html coding but aren't working in web design?
4) Movies can be bad for a thousand different reasons and a bad screenplay (from a new "talentless" writer) is just one of them. Most screenplays that are bought are rewritten a number of times (before they go into production - often during production even), sometimes by the original writer, often by other writers. It's not uncommon to have dozen and dozens of different drafts of a script, some of which may bare little resemblance to the actual shot film. Unless the new writer changes more than 50%, they do not get screen credit. So many movies have more writers than their credits would imply. In addition, some writers will change a lot in an original screenplay (whether needed or not), just to get screen credit. Executives, producers, the director, even actors will want input in the script if they can. Too many cooks in the kitchen... Anyway, blaming bad movies simply on new or "untalented" writers isn't fair or accurate at all. Yes, there are bad scripts that get made into movies, but more often than you think, there are other factors that made the actual movie and/or script bad. And as sad as it is, a lot of those really "bad" movies, make a boatload of money. So if you wanted to blame anyone, blame the moviegoing public that pays to see them.
Good luck to you in any case!