Yes, that's the endgame, an Android device in a drawer at home. But what do I have to carry on my pocket to use the minimum amount of apps? Firefox, WhatsApp with video and audio calls, Telegram no video no audio, a mail client, a YouTube client (possibly not from YouTube), a maps and navigation app (for cars), phone calls, SMS.

YouTube on Firefox is a much better experience than the official YouTube app, so you can drop one from the list.