Part 2. BTW, None of these are anything new, We The Community have mentioned all of these things numerous times and they are being ignored or argued against.

"Just give people instructions on how to find the freebie/tutorial using on-site search (e.g. on ShareCG), Google, or Bing"

In many cases this simply does not work.

1. Not everyone is skilled/talented at using search engines. In order to make instructions friendly to them, it would have to include in-depth instructions such as "Copy and paste this query into the search. Click on the 5th result that comes up. Now scroll down to the 16th thumbnail on that page" Instructions are even more complicated for sites that redirect you to the homepage if you reach it from a search engine. The person giving instructions may not be able to figure out how to find the page via Google/Bing/etc search, either.
2. The link to the freebie/tutorial may be too far down the hit results list.
3. Some people use Googledrive, Skydrive, or Dropbox. Saying "well, then, upload your freebies to our site" is not a valid argument because those freebies usually belong to someone else.
4. This is a community. One of the MAIN PURPOSES of community forums is to help one another. Banning off-site links, esp. to tutorials, is counterproductive to fostering the community. The argument that we should upload tutorials here again is not valid because said tutorials are rarely ours, and most of us lack the skill needed to make our own. Saying "use someone else's for inspiration" is also invalid because the tutorial creator might require such tutorials to link back to their tutorial.
5. Sometimes a person is in need of a video tutorial. Not everyone knows how to make videos.

"There is no reason for people to upload freebies to other free sites and then post a link here/in Free Stuff. We allow unlimited number of uploads of up to 200 mb per file."

There are many reasons why someone would do this.

1. Many people find it either a hassle or too difficult to upload freebies to this site ever since last summer's redesign. This is likely one of the major reasons why you are seeing far fewer uploaded freebies.
2. Some people don't like the fact that you have a "must be Winzipped" rule. ShareCG allows rars, 7z's, and non-compressed downloads.
3. Some people don't like the 200mb size limit. Or maybe it's more that they don't like some previous size limit, and are unaware of the current one.
4. Someone said that you can only upload one freebie per day. Is this true? If so, then that would be a major reason.
5. Some people have personal websites that include their downloads as well as a blog and/or tutorials, which they may want to direct traffic to.
6. some people use Googledrive, Dropfile, Skydrive, etc. to upload their links. This saves them the time and hassle of uploading their freebies to multiple sites such as their blog, someone else's freebie site, the Daz Forums, and Renderosity, for example.
7. some people have a personal marketplace website E.g. Pretty3D's Artraiders, and may want to direct traffic to it. This is almost entirely a thing of the distant past, of course, since it is no longer lucrative to do this, so people almost never do, anymore.
8. Some vendors have off-site galleries. They may not like the promo and gallery size requirements on Renderosity. This is especially true for non-exclusive products-- it's a lot easier to just link to an external gallery rather than upload extra promos to galleries of multiple marketplaces.