Oh yes, I also hate the current trend of not caring and basically saving money by 'outsourcing' your programmer wages out to users' CPU, RAM and electricity, especially when done by always-on premium apps made by multi million/billion companies (*cough*
Slack *cough*) that should really know better.
Perhaps some more GUI-ish language + toolkit combo like C with GTK+, C++ with Qt, Free Pascal with Lazarus, etc. would be better for a more utility-like OS-integrated application. They come with better OS integration, tray support, lazy redrawing, software rendering, drag and drop, copy paste, native-ish GUI components, etc. out of the box.
In Task Manager my Pascal* program Botes uses 8 megs of RAM and no CPU at rest despite storing like a meg of text plus having a GUI window with a code editor and few controls open. I'd never write such a program in SFML though.
OBS actually uses Qt which is of course heavier than pure WinAPI GUI would be but it's still good and small enough memory and CPU wise so it's OK. Going for top optimization makes no sense a lot of the time. I just opened obs64.exe and it takes 100 megs, and of course for recording or streaming you're supposed to actually have a beefy machine because these programs aren't cheap on memory, CPU and network/disk so using Qt and taking 100 megs at rest is meaningless in comparison.
In 'normal' consumer device world (i.e. not programming on an integrated controller that has half a KB of RAM) you need to strike a healthy balance instead of going off one deep end and frustrating performance aware users or another and wasting your time chasing optimizations that won't affect anyone in practice.
* I think Game Maker is or was in Delphi (another Pascal that Free Pascal and Lazarus are largely compatible with) actually.