I don't know these were posted or not but here is my suggestions which every youtube watching person probably already heard about most of them:

Not Just Bikes: Channel about Urban Planing-Living and how destructive the cars are.

History Matters: Short animated videos about historical events, narrated with humor.

my mechanics: Best and most detailed restorations ever.

NileRed - NileBlue: All about experimenting with chemical reactions.

Oversimplified: Like the name, oversimplified narrations of historical events but in a long form with animated depictions and humor of course.

Stefan Milo: Really informative research videos of archeology.

The Linux Experiment: Like the name suggests it's all about Linux.

Bad Lip Reading: It's in the name.

ChrisFix: Best car repair channel out there.

DIY Perks: DIY videos but heavy on the entertainment side rather than the doable diys.

Ethan Chlebowski: Trying to understand cooking from the perspective of homecooks.

Alex (the French Guy Cooking): Reverse engineering the recipes.

Brick Experiment Channel: Building Lego machines.

These all are high quality channels imo. There are a lot more but I am kinda lazy for now.

This is a csv file of really high quality channels that you can directly use in Piped: Proton Drive Link to csv file