Like what?

BTW Forza games only have the assists on if that's the difficulty you choose. At the beginning of the game it asks you what your experience is and you pick accordingly. 

There is another video of Forza 5 of the Prague demo where the guy that plays it turns all the assist off.

you can change some of them in the demos. watch some of teamvvv's videos on youtube as example. he doesn't always play without assists but he tried different settings at gamescom and wherever else he played forza 5 demos. but the demo doesn't seem to have all the settings if i remember correct.

and what can't you change in forza which you can change in gran turismo? not sure right now since i didn't play gt5 for a while.

I can't say about Forza 4 because I played it few time compared with a lot in Forza 3... Forza 3 have a permanent steering assist that can't be turned off.

I really didn't tried Forza 5 Demo but when I tried the Forza 4 Demo years ago a lot of options for turn off are not present... so I think the same happened with Forza 5... I can't be wrong.

And most videos I saw for Forza 5 was using Xbone controller... you can't turn all off when you choose controllers.

OK, yeah I know what you're talking about. Forza 3 didn't have an option to turn on simulation steering whilst Forza 4 did so it's pretty safe to say that Forza 5 will allow it as well.

Oh and I actually remember seeing a video where the guy turned off the assists for Forza 5 as well. So you definitely can turn them on or off but I believe you have to go into the settings to do so.

EDIT: Nevermind you can easily change the assists in the demo.

http://n4g.com/news/1344964/forza-motorsport-5-hands-on-taming-a-mclaren-p1-with-no-assists-team-vvv

The guy was playing it with a wheel and he did turn them off himself, he wanted to so to get a better feel for the game.  He did pretty terrible in his first try even though he is pretty good in racing games.  He was using the P1 and is real life the car comes with a lot of driving assist.  I post the link to it later if I can find it again.

Here it is his whole channel is about racing games:

http://www.youtube.com/watch?v=OnMIq6LTvJA

That sounds like the link to the video I posted in my previous comment :P

It is the guy has a pretty good Youtube channel and his own website all about racing games.