Just to add what you mentioned, there is also an issue with Mobile updates in the background gobbling up cycles and RAM, when combined with say the zoom app, running multi-party or even 2 party, these items take longer and can/will slow foreground tasks, like screen sharing where the host is displaying/reading from local storage, or worse yet sharing tight VNC view to help someone with a support issue, lots of nasty secondary and exception use cases out there, and a few primary which will quickly hamper the foreground task.
The solution is software int. controlled write to local storage , which uses per process/app queuing, concatenation of the session write blocks, then single block session write to store... to get within 95% of the actual media write speed... , this works w/ VRAM setups as well, when you are RAM constrained, the VRAM block writes by the OS get super fast,
It's what we do at cloudprox.com on Ubuntu in the DCs and Colo space at the moment (to actually get remote workplaces to work at scale with fast IOPS/Gbsec without breaking the bank) , we are looking at how to bring the same fast write functionality on to Mobile and IOT devices, as it is indeed the choke point for everything, and will easily turbocharge ubuntu touch environs by at least 5X
plus your media lasts 5X to 30X longer, and you use significantly less battery, it's the OS juggling between threads and processes which kills your battery life.
r2