Time on task matters... a lot.
Honestly, I can't think of a single thing where time on task does not matter.
Want to be better at squatting? Squat more.
Want to be more flexible? Stretch and move more.
Want to be better at math? Spend more time doing math!
Is this a revelation? Of course not - it's simply an extrapolation of the SAID (specific adaptations to imposed demands) principle. It's strange because, for whatever reason, people in the fitness, strength, and conditioning fields (and just about every other field for that matter) seem to spend a lot of time and energy trying to AVOID the one thing they often need more of which is time on task.
This isn't the first time I've referenced this chart that appeared on the Supertraining listserve quite a few years back now, but take another look. It reflects a trend towards less total training hours on the part of elite athletes in various sports.
From: Block Periodization: Breakthrough In Sport Training (Supertraining listserve)
I believe there are two takeaways from this chart; one is that training time among elite athletes has indeed changed - we could point to a number of reasons, but likely training and recovery methods, how training time is computed, and a lower tolerance towards work hours in general are not a small influence. The second takeaway is that elite athletes are still training a thousand hours every year! There's a lot of talk about the 10 years/10,000 hours needed for mastery these days, but people somehow gloss over the 2.74-hours-of-training-every-single-day thing. We can say "quality over quantity" and placate ourselves into thinking that somehow, because our practice is mindful, we can get by with fewer hours and more days off in the gym or on the field, but sometimes less is NOT more. Sometimes less is just less. Something to consider...