I'm running Plasma on a low-range laptop from 2010 and it runs exactly as smoothly as it does on modern hardware. It was $600 in 2010, has 4 GB RAM and one of the earliest generations of the Core i3, with integrated graphics.
If your acquaintances have machines that struggle to run Plasma, I'm honestly surprised they can run graphical apps written in recent GTK or Qt versions at all.
In many cases, Plasma's going to run better/smoother than these "lightweight" window managers and desktops. Because, all the Stockholm Syndrome-ing about "simplicity" often translates to "probably is single threaded and does more CPU work than it should because it's easier." In my experience, they'll tend to have worse vsync issues and tearing.
I doubt i3 is actually drawing shit on the screen faster than Plasma with animations off.
>[..]In my experience, they'll tend to have worse vsync issues and tearing.
Thankfully I've been able to avoid that for the most part, but I will say it's certainly easier to avoid with plasma's compositor.
>I doubt i3 is actually drawing shit on the screen faster than Plasma with animations off.
I'd definitely be interested in a raw speed comparison if there was a good method/benchmark, but I don't think that has ever been my limitation (although if I were running on lower spec hardware everything counts)
Plasma certainly has more features, but it's still definitely heavier than i3 (or most (all?) tilingWMs), LXQt, icewm, and the like.
On decent hardware there's not a huge point other than preference, but when you've got 2GB of RAM and a 12 year old CPU every bit helps https://i.imgur.com/vZszQFE.png
In the case of a simple window manager like i3 I cannot imagine what it would need to do in a second thread and without a compositor it would definitely be drawing faster if not perceptively faster. I don't think one would be apt to notice any difference in performance save for plasmas still slow startup.
I could I suppose point a camera or a phone at the screen and measure I suppose.
If your acquaintances have machines that struggle to run Plasma, I'm honestly surprised they can run graphical apps written in recent GTK or Qt versions at all.
In many cases, Plasma's going to run better/smoother than these "lightweight" window managers and desktops. Because, all the Stockholm Syndrome-ing about "simplicity" often translates to "probably is single threaded and does more CPU work than it should because it's easier." In my experience, they'll tend to have worse vsync issues and tearing.
I doubt i3 is actually drawing shit on the screen faster than Plasma with animations off.