I recently put Alpine with i3 on a Raspberry Pi 4 Model B and I'm super impressed with how snappy it is. I find it much better even than Raspberry Pi OS Lite.
Same here, I put it on two very old RPi 1 and was amazed at how low the footprint is. I wish there were images available for other SBCs as well, mostly Allwinner based ones (OrangePi, NanoPi, etc); probably I did something wrong but building them from scratch turned out more complicated than expected.