You can use a DNS based solution on iOS. It's easy for WiFi and there are apps that can change it for the cellular network as well.

I was previously considering to make my next phone an iPhone (better integration with my MacBook), but I recently discovered Youtube Vanced and realized that if I'm ever going to watch non-trivial amounts of Youtube on my phone it might be worth it to stay on Android just for that app.

Pythonista on iOS can run yt-dl, works well