Of course there was an "eye candy" element, but when hasn't there been in television? TV shows hire attractive people of both sexes. TOS has its crewwomen in miniskirts and alien women in flimsy strips of fabric, but also had Kirk gratuitously lose his shirt on a regular basis. We can complain about the implausibility, but it's a fact of life that TV shows are cast good-looking people and play up their attractiveness. So yeah, Seven's and T'Pol's catsuits were particularly egregious examples of that, but I saw them as basically par for the course. And while I deeply enjoyed looking at Jeri Ryan in her catsuits, I never had a problem noticing what a gifted and charismatic performer she was as well and what a rich, intriguing character she was written as.