I'm a wlroots developer, and I'm using an old Sandybridge mobile i5 CPU daily. So I'm pretty surprised about this. I'd be interested in a bug report if you were to try again.
I'll agree with this post. Wayland is not pleasant on my core i5 machine either. I should point out that the GPU it has is very weak, I don't know what it is but most 3d games are unplayable.
X.org, Firefox, and Xterm all work very well on it though. As do other apps like gschem and openscad.
"Wayland" is just the protocol, can you give more details about your setup? For instance, GNOME is more heavyweight than say Sway (and gives a more feature-ful and eye-candy user experience in return).
wlroots performed very poorly on my i5-3427U with 4000 series iGPU. Very poorly. I ended up using neither X nor Wayland and instead having mpv render straight to the frame buffer (--vo=gpu --gpu-context=drm)