Not going to add description of the channels or links, and many don’t have new videos because they are old channel but with some good content:
LearnLinuxTV
KDE Plasma tips and tricks
DB Tech - Main Channel
The New Oil
Shichimi archival channel
Linny and Winny
Krita Tutorials
Privacy Guides
Techlore
(RTP) Privacy & Tech Tips
Free Software Foundation
Trafotin
Veronica Explains
Surveillance Report
Mental Outlaw
The Linux Experiment
Tip: you can subscribe to all of those using Grayjay in your phone and watch it in a convenient way
Just a few more:
Chapada dos Veadeiros
Chapada da Diamantina
Chapada dos Guimarães
Pantanal
Amazônia
Fernando de Noronha
Those are probably the most famous but there are much more from where those came from.
Complete list.