When it does support it, probably very well. iPads could support editing and playing back multiple simultaneous 4K video streams long before desktop Macs could

When it does support it, probably very well. iPads could support editing and playing back multiple simultaneous 4K video streams long before desktop Macs could due to the huge bandwidth between cpu, memory and gpu of A series chips. M chips dialed that up to 11. As to your storage concerns USB-C iPads, apart from having up to 2TB of internal storage and up to 16 GB of memory, support external drives just as well as any laptop. The time when high end iPads had below low end desktop specs is long gone.