I've always been an iPhone user and have never seen a .txt file on one and probably you wouldn't be able to edit one on an iPhone if you did have it in Files app - I'm not counting Notes app as a text file here.
I do quarterly notes inside of Notes app but it mostly non-work related stuff and doesn't integrate well with desktop since its kind of a pain to login to iCloud from browser. Quarterly notes bc once the note gets too long, it gets very laggy on phone and is difficult to navigate; i.e. getting to the bottom to write a new line can be tough on mobile.
The slippery slope is long behind us, we're already at the bottom.
Why not something like c#: native, fast, crossplatform, strongly-typed, great tooling, supports both scripting (ie single file-based) and compiled to a binary with no dependency whatsoever (nativeAOT), great errors and error stacks, list goes on.
All great for AI to recover during its iterations of generating something useful.
Genuinely perplexed.
Also, this guy is calling HTML a programming language. Make of that what you will...