But...Voyager's ratings weren't holding strong. They were declining exponentially every season.
Voyager had a habit of focusing more on making an exciting commercial than actual good writing. The episode with The Rock is the biggest example of this, that episode got much higher ratings than most episodes that season, but the viewers who tuned in to see The Rock didn't tune in the next week. All Voyager seemed to really care about was what would get people to tune in that week, not what would cause long term fan loyalty. Even though the show was more accessible than DS9, DS9 had consistently higher ratings, because it did more to establish fan loyalty.
TNG on the other hand was so successful because it managed both. It was accessible and knew how to write a good commercial, but also knew what kind of writing would create fan loyalty.
And Enterprise's first two seasons were far worse than any other Trek's first two seasons.
Voyager's ratings didn't drop low enough that couldn't do it's intended seven year run. No Voyager didn't hold TNG numbers(no Trek or any other show in syndication before it ever has) but it wasn't in danger of cancellation either. If Voyager got voted to be the 1# Trek show to seen on Blu-ray, then I'd say there's plenty of fan loyalty behind it. It's tells me and Paramount people are still willing to pay for it, again! If Voyager didn't create fan loyalty, then it wouldn't have even held enough ratings to continue for as long as it did and it wouldn't sell and still be selling the merchandise it does. Voyager also has many fans that weren't into Trek before but the laid back style of the show appealed to them (or Seven did)or new fans whom Voyager was their first introduction into Trek.
What also has to be considered is where and how Voyager was shown at the time for it's ratings. In many major cities across the country, Voyager ran at the same time as DS9(on different stations) causing Trek fans to choose which to watch. Many stuck with DS9 because they were already 3 seasons into it. In other major cities, station programing didn't carry UPN or Voyager at all. So how was a show to have ratings that were truly competitive if it isn't being shown everywhere? TNG & DS9 were accessible in far more stations nation wide, thus being allowed to be shown in more households. With that in mind, Voyager is impressive to still hold the audience it did and to last it's full run being carried by less stations and in fewer households. Voyager defied all the odds against it and still succeeded.