Data caps make that hard. While everyone likes to claim unlimited data, I'm not aware of any providers that don't have a heavy data user clause where they'll deprioritize your data if you're a top ~5% data user (usually somewhere over ~1TB/month).

You also will need _some_ sort of encoding locally before uploading, even if it's minimal, which could lead to issues when encoded again (although there are codecs available to minimize this).