Who else will follow?

The US legal history goes back further than the founding fathers. I guess it's safe to assume that the Statute of Anne had a major influence on US copyright legislation (according to Wikipedia, they copied it almost verbatim). I'm neither a lawyer nor a law student, but I think we can view British and US copyright law as one legal tradition then, which started with the early printer monopolies of the 16th century.

Also note that the US constitution doesn't mention the term "copyright" and is pretty vague about the rights that are secured to authors and inventors, and under which provisions. So the constitution doesn't tell us much about the reality of copyright protection.

...this is coming from the same company which tried to force their own new hypertext markup language upon the world.

Also, we don't have a single world language in the literal sense, and much less when it comes to video formats. Complaining about a browser (with a 10-12% market share, mind you) not supporting H.264 is like complaining about people on the web who are not speaking English.

Whatever you may have heard about such idealistic intentions of copyright is pretty much bullshit. The original idea behind the Anglo-Saxon term of "copyright" was just that - the (exclusive) right to copy something. Its primary purpose was to protect publishers from competition (made possible by the invention of the printing press) by granting them some exclusive rights, e.g. on printing and distributing the bible. This was the 16th century. So, nothing has really changed, just the rhetoric.

What you're referring to are author's rights, a term mostly used in Continental Europe. I don't know whether the intentions behind them were even as benevolent as you think. And in any case, Continental and Anglo-Saxon ideas about copyright/author's rights have conflated in the last decades/centuries, anyway.