I was surprised to see this headline, because I had been using Plasma 5 on Intel graphics for almost a decade without any issues. After reading the article, it

I was surprised to see this headline, because I had been using Plasma 5 on Intel graphics for almost a decade without any issues. After reading the article, it turns out that this is about Wayland, and I used X11. Wayland was indeed quite laggy when I tried it once, it's good to know it is solved now.