Firstly 50MB isn't ".5G", it's 0.05GB (you're out by an order of magnitude).
You're point about not tracking current is relevant though....or at least it is for some domains. When it comes to multimedia authoring you do expect people to running at least current systems because multimedia authoring is hardware heavy processes thus professionals will invest in the hardware to support them. Even weirder is the expectation that you'd want to be running a hardware heavy web-browser while running your hardware heavy authoring tools on those modest systems. That feels like you're making some unfair demands tbh.
As for KDE5, that runs fine on older hardware. I have a 7 year old laptop and KDE flies.
You're point about not tracking current is relevant though....or at least it is for some domains. When it comes to multimedia authoring you do expect people to running at least current systems because multimedia authoring is hardware heavy processes thus professionals will invest in the hardware to support them. Even weirder is the expectation that you'd want to be running a hardware heavy web-browser while running your hardware heavy authoring tools on those modest systems. That feels like you're making some unfair demands tbh.
As for KDE5, that runs fine on older hardware. I have a 7 year old laptop and KDE flies.