Have no doubt, even truly creative works would suffer, since there's no incentive for investors to invest even in truly creative work, since there's no monetary return on investment - just a movie which they can't monetize.
Imagine if George RR Martin had to hold a day job in addition to writing - how many books would he have actually written by this point?
In my experience, in recent years I've found to enjoy lot more independently produced content (which either happens to be free or very cheaply available) as opposed to big budget titles produced by big corporations. Not because I actively seek such content, but because I genuinely find it to be more worthwhile and enjoyable than the other option.
Now I can't really speak for motion pictures, because I don't watch tv shows and movies anymore - but I can definitely say this is very true for the music and video game industries - big investment and quality are not correlated.
In fact, an argument could be made using those same movies as an example, that these excessive IP laws have the exact opposite effect and actually end up stunting creativity and originality as the big corporations aim to milk every last penny from decades old franchises and ideas, instead of seeking new and original concepts, because the former is a far more profitable endeavor. I mean, look at the state of Hollywood right now - when was the last time you saw a truly novel and noteworthy movie, not based on an already established franchise/idea/series?