TF2 has a ton of really amazing and well made community items. TF2 also has a strict art style. I know, I know, people always rag on how the art style was killed, but outside of the promo/holiday items, pretty much every community contribution fits in with the 60s sci-fi theme, not to mention graphical issues such as shading and lighting. They also have to tie into the character's personalities and background. A lot of people also strayed away from making weapons, because before they would be implemented, Valve would have to figure out how to balance it. Dota 2 is certainly more free due to the fact that there are dozens upon dozens of characters, it's fantasy so you can really create anything, you don't have to balance weapons, Dota 2 is constantly growing so it is a big market, and Valve puts in cosmetics at a much more rapid pace than they ever did in TF2 so people keep churning out items to meet the demand. You can really never "run out" of things to model like in TF2 where the items have some basis in the real world.
there's a number of reasons why Dota 2 gets more items and better models than TF2
- They accept higher poly models and more detailed normal maps. TF2 doesn't really have many normal maps, and comparably the polycount of Dota 2 items goes a lot further than TF2. On Dota 2 you might have a low limit on bracers, armor and boots, but in TF2 you have to combine all three because TF2 only has 2 misc slots and that lowers the overall budget you have.
- Dota 2 has a wider variety of styles and item types. TF2 has weapons or clothing. Dota 2 there are heroes like Tidehunter who can have organic items like fines or scars, or clothing, or weapons, and those weapons can be teeth on a piece of driftwood and it makes sense. Something like that would look ridiculous in TF2. I noticed with TF2 modelers who work on Dota stuff, that they seem to like the organic items, because you can't make scars or fins or spikes in TF2 so they make fins, legs, carapaces, etc.
- Dota 2 has a bigger team than TF2. TF2 has 15-20 people. Dota 2 has like 75-100.
- Dota 2's models are easier to compile for the user and easier to implement for Valve. For Dota 2 it's basically copy and paste to implement. For TF2, the steps to add a single hat can take hours (where it's minutes in TF2). Someone at Valve said they can get through browsing 60 items a day in Dota, but only 6 in TF2 on the workshop. This means even 9 item crates can take a whole week to put together in TF2, while in Dota it's probably an hour's worth of work. For reference the last time TF2 had a whole item set added was last June. The last batch of community items for TF2 was in December and it had the same amount of items as one weekly patch for Dota 2.
- Because of that, it's just wiser to make Dota items. You can make a great set and have it in-game in a week in Dota. In TF2 it could take months, if not years, to see your set (or just one item from it) added to the game.
- Dota 2's items are better optimized than TF2. In Dota 2 each hero has a base model and pieces are added to it. In TF2, every class has a full model and pieces have to be built on top of it. So everything looks bulkier and you don't have a lot of freedom to make extremely different things. Shirts have to be modeled over existing shirts and you have to get super creative when making items that show flesh because they'll seem really bulky (because they're modeled over clothing).
- TF2 also doesn't have any system to allow custom animations, Dota 2 does, so this limits what can be done with TF2.
- Because of that point, TF2's weapons are kind of limited. While someone like Brew can use the same animations for a flail, a stick, a shovel, a wrench, etc, in TF2 if you only have shotgun animations, that class can only get shotguns. Even the melee animations are oddly specific (Heavy can only get fists, Spy can only get knives). This is probably because new items in TF2 were hacked into a game that wasn't built with it in mind, so everything is super specific. Some classes, like Heavy, have a stupidly small set of animations, it's hard to make weapons that aren't just variations of default. Even "generic" animations like the all-class one hand melee animations are really specific to certain items, and near useless.
- Weapons in TF2 need sats. They don't in Dota 2, so people can go wild with weapons and not have to wait for the once in 3 month patch TF2 gets with weapons.
There's a lot of things each game could offer the other though. I prefer TF2's method of accepting individual items, and in the case of sets, ignoring weak elements of sets and just implementing the best parts. Dota 2 is so set heavy now that individual items are rarely accepted, so everything has be a set and in some cases this makes for weak items just to make a set. I'd love to see them make 4-5 bundles of items rather than sets. So they might accept 5-6 items and make them into bundles and be added like sets are right now. This would allow for many more heroes to get a variety of items, while still offering a bundle (so maybe 2 uncommons, a rare and a mythical in a 9.99 bundle)