I think that's the main reason.
Reliance on triple jumps probably also self-selected for smaller body types than figures-era skating.
"like" Caryn Kadavy or Holly Cook in what sense? I don't think of their skating as being very similar to each other. Because I think of Kadavy as being much more polished, with more coherent choreography.
Speed and attack specifically?
No, I don't think that is considered juniorish.
Athletically talented skaters may rise to the top at young ages, straight out of juniors, on the strength of power/attack and triple jumps, and then if they stick around become more polished as they mature. So in that sense, reliance on athletic ability more than refined skills might be associated with younger skaters.
But a lot of younger junior skaters who are not ready to compete with seniors in their early teens (and may or may not ever get there) don't have as much power because they don't have the muscle mass and/or highest-level stroking skill yet.
The best seniors have both power and refinement. They may be just as fast or faster as when they were juniors, but not look like they're attacking as much or working as hard because they achieve their speed more from technique.
Here are two freeskates by the same skater at 17 and 23 years old, which both happened to earn fourth place at post-Olympic Worlds. She was always known for her speed, but at the older age seems to harness it better. Does that come across as less attack?
Well, both Caryn and Holly seemed peppy. Maybe the superior stroking skills of skaters today make them appear to skate slow when they are actually skating fast, but I don't know why they would want to do that. Most of the music they have been picking out is horrible, although YMMV, of course.
I would rather see a program like Caryn's or Holly's than the graceful, slow, tortured-looking interpretation of a single violin playing an obscure, tuneless classical piece or an annoying guitar that gives me a headache. I'm looking at you, Ashley Wagner.
I'll put up a video tomorrow, right now I have to go to bed!