For certain styles, a fretless bass sometimes fits better sonically, e.g., folk, blues, Americana, most types of jazz, anything with lots of synthesizer in it, etc. On the other hand, certain styles, e.g., electric funk or anything requiring a lot of slap, sound better on a fretted bass a lot of the time. Different tools for different needs. Some people really like the sound of a fretless bass played with a plectrum.
On the other hand, I find that in a rock band I most often reach for a fretted bass.
Yup.
Totally possible to play power chords on a fretless, but not easy.
A root-five chord on a fretted bass is way easier to hit consistently, and sounds great on rock/prog/metal/punk tracks.