I wholeheartedly second this recommendation. I love that channel, and I don't even understand why. The videos are incredibly soothing and pleasing. They speak to the craftsman in me.
Apparently Baumgartner and his techniques are under some criticism from other restorers, but all I could find was a somewhat angry Reddit thread.
https://www.youtube.com/channel/UCvZe6ZCbF9xgbbbdkiodPKQ
It's extremely relaxing to watch. I guess I chose to wrong profession.
If you understand German, there was also a good 45 min documentary about a restaurator a few weeks ago on SWR:
https://www.youtube.com/watch?v=6-hbYKyyWiI
His gilding skills are superior to Baumgartners.