Upload to YouTube?
I doubt it (although I have nothing to do with this project). These videos, while now twenty plus years old, are like abandonware - they exist in a grey copyright area. They are probably still technically still under copyright, but in most cases no-one cares (even the creators in some cases) as the information on them is so old. I would suspect that some of the creators would even appreciate the archival effort.
Not sure YouTube would be the place for them.
Anyway, by the time you've watched a full hour long video on YouTube, you've streamed about a gigabyte of data, so downloading a gigabyte beforehand isn't much different (six of one, half dozen of the other). Plus, if you need to rewatch on YouTube, you have to stream it all over, whereas with the download, it's only once and you can watch it over and over again.