I think that limit is quite sufficient because people won't want to watch the long documentaries/video presentations.

Yeah, People won't want to watch the long presentation but it gives benefit for advertising......

Very good point. But if the vendor/business decides to upload instructional videos on how to use the technology/product, it now has the option to upload bigger files.

However, uploading a 2 GB video may take me forever...

With the technology evolving (and the infrastructure and connection speeds ever increasing) I think it's a no brainer:
If you post something of value (personal or commercial) people will gladly spend the time and money to watch it. For example online product demo's. This in itself could be a cost saver in many ways? The people that put 2gb worth of non sense onto youtube will be waisting there money with only themselves watching it. We are a smart people, held back by a money hungry world.