In no particular order:
- The Rest Is Science (podcast)
- Technology Connections/Connextras
- Jeff Geerling / Level 2 Jeff -- Edit: see replies below
- Techmoan
- Gamers Nexus / GNCA
- LGR
- Switch and Click
- The Linux Experiment
- Tasting History with Max Miller
- Ben Eater (breadboard computers)
- Stuff Made Here (engineering)
- Up and Atom (science)
- Simon d'Entremont (photography)
- Words Unravelled and Rob's Words (English language)
- Kurzgesagt -- Edit: see replies below
- Veritasium -- Edit: see replies below
- Tom Scott (the returned)
- Asianometry (tech history)
- Clabretro (retro networking and server hardware)
Edit: A few bonus channels that may be of interest but didn't all fit the criteria for me:
- Action Retro - doing silly stuff with old computers - more recent discovery for me
- Dr Geoff Lindsey - Linguistics - I only watch occasionally - can be a bit heavy on the linguistic science for an amateur like me.
- Lftkryo - Linus Åkesson - an absolute wizard coding on the C64
- RetroBytes - computer history. Most of his content is mainly him just talking, so I can just listen while I'm doing something else
- Tech Tangents - more of a recently discovered channel for me. Vintage hardware. Underrated channel.
- Serial Port and Parallel port - vintage computers and networking. Brings back memories from my days working for an ISP.
- Honorary mention to Veronica Explains. She keeps things pretty basic so I don't get a lot out of her videos, but I like her stance on open source and not selling out. She posts everything on Peertube as well.