I’ve seen lists of songs with deep lyrics, songs that are upbeat but depressing at the same time, songs not on the radio, and other things like that… But I have never seen a list of songs that are just super fun to sing.
Some examples of things I like singing are Lewis Capaldi, anything by Chris Cornell (though I wish I could have that awesome gutteral/growly sound in my voice), Cottonmouth, Nirvana, RHCP, Tool, etc. I love long sustains and just dudes and dudettes belting out staccato. The feeling of matching pitch and tone you get in your stomach and lungs as the sounds reverberate together is exhilarating.
My gotos:
Old school == Best school, IMO
So many people across different demographics get into older songs, regardless of genre. The best songs to sing are ones that you can hit the notes and not put the crowd/your friends to sleep to.
Have fun with it!