To be fair, Power Rangers does have a long history of Civilian super-powers.

Andros in In Space had telekinesis.
In Time Force, Katie was super strong and Trip was a Psychic
The Dino Thunder Rangers all got super-powers from the Dino-Gems (Supersonic Shriek, Diamond Skin, Super Speed, Invisibility, etc.)
The SPD Rangers were all mutants with weird powers like Jack being Intangible, Z being able to multiply herself and Bridge could sense aura's.
The Mystic Force Rangers were all wizards and could do magic n shit.
In the Reimagining movie, the armour was just armour and they were all super-strong regardless.

So, yeah, Civilian Super Powers were pretty common. Especially during the Disney Era. Apparently, Disney wanted to push the civilian powers thing hard to try and cut down on the amount of Sentai footage and to replace potentially dangerous fight choreography with cheap CGI. Plus, Cheap CGI is harder for kids to hurt themselves trying to recreate, making the show more lawsuite friendly.