Compression is waaay more effective, so if you have to pick one, go with compressing. Is having readable source code worth the other 2KB? That's up to you. Source maps can do the same thing with less, though. Also, modern devtools have ways of de-minification (if you don't mind all the mangled variable names).
In the example given:
Original - 147 KB
Minified - 123 KB (83%)
Gzipped - 22 KB (15%)
Both - 20KB (14%)
Compression is waaay more effective, so if you have to pick one, go with compressing. Is having readable source code worth the other 2KB? That's up to you. Source maps can do the same thing with less, though. Also, modern devtools have ways of de-minification (if you don't mind all the mangled variable names).