That sounds brutal if you have 5 years of daily uploads or something like that. At some point, if you want your entire catalog, that becomes a very sucky process.

Just use Google Takeout. It will create a series of archive files for you to download.

Surely you would have the originals locally and not rely on youtube to archive yours uploads?

People who do this are a minority. The vast majority have the masters only available on YouTube.

I hope your “surely” was in jest.