Why things might have taken so long
About not having invented anything: it's harder to invent something novel today simply because so much has already been invented and knowledge of it is available.Centuries ago, it was easier to think of things to invent (we should be able to fly, to stay under water longer, to copy books faster, to notate music… ). It still took a lot of work to actually realize the invention (which only could be done by people wealthy enough to dedicate the time or get patronage from a wealthy source).Today, we've run low on the scope of reasonably easy to invent things that are actually valuable. All the obvious "wish we could X" things have been done or are nigh impossible for any one person or small team to figure out (or flat out impossible). Innovation in areas like AI or medicine or battery tech — that stuff is all being actively worked on and requires massive funding of teams of advanced specialists. We're not going to see some person just invent something around these things the way multiple people independently invented forms of rope in prehistory.