I have watched it halfway through and so far some hot takes
Rust ecosystem is a little messed up to interact with for him at least
Zig fixes the pains of C, the build ecosystem (handles the compilation for us), and package management (like go)
Project-based learning for the win!!
He started to build Ghostty as a fun toy project, then found some pain points and tried to fix those with an ecosystem of libraries to build an abstraction layer of apps on top of terminal emulation.