Being an artist is alot like working out at the gym.
We all got our own goals and reasons for being there. Some are focused on strength training, and some are focused on bodybuilding. Some want to be stronger, some wanna be faster, some want better endurance, some just wanna look good. Some want to get better so they can compete better in a sport or some other event. Some just like the Euphoria of working out, or just do it to relax or as a form of "meditation".
For some of us its all of those things.
Some only hit the weights, some only do cardio, some of us do both. Many of us adjust our diets, some don't. Some of us workout nearly everyday, some people workout only a few times a week. Some of us find a lot of inspiration in music, some are distracted by it.
There are many ways to get to where you wanna be. Most people who know what they are doing, walked a Path that helped them get the results they wanted, that may or may not be similar to your own Path. Sometimes these people offer advice to others to help them understand things that could help them improve, based on personal experience, but their goals may be different than yours. Maybe your focus is bodybuilding and their advice is more related to strength training. It might be very beneficial advice but not quite in tune with your goals or Focus.
But if we see someone at the Squat rack fucking leaning all the way forward and destroying their back, we might feel obligated to help the person see what the fuck they are doing wrong. If someone is doing curls and they are swinging their arms like chimpanzees and using momentum to cheat themselves while grunting like King Kong, someone might point out that they aren't really working out shit. If someone is bench pressing and they they had too much weight and can't get the bar off their chest, struggling to breath and looking around for aid, I'll help them get that shit on the rack.
Anyway
Obviously you are more likely to trust the workout advice of someone who as revealed proof that they are indeed strong, healthy, and athletic. But just because they haven't uploaded a photo or video of themselves, perhaps to maintain the discretion of their identity, doesn't mean that their advice is irrelevant. A good athlete or bodybuilder can contemplate and visualize the effects of their advice and would know whether or not it would be a good idea to integrate that into their workouts. They may even experiment with it the next time they are at the gym. If it works, great. If not, oh well. Everybody is different, and maybe your goals for working out are completely different than theirs, and thus your training should be.
I've given advice but it is by no means absolute. It has worked for me personally, and for other artists who use similar methods of creating their Art, who shared similar goals.
I have absorbed good advice from artists and discarded good advice from artists, depending on how well that advice resonated with me, my artwork, and my goals. You Will to do the same. As you should.