when it works it's amazing. but very often both my phone and laptop are connected to the same WiFi, yet kde connect can't see them. I can't figure out how to diagnose and solve that when it happens
Very typical for my KDE experience. Things break and it's impossible to figure out what's gone wrong b/c there is no additional information/logs/diagnostics exposed to the user. Everything to do with Networking and Bluetooth is plagued by this (though to be fair things break a lot less than ~5 years ago)