First, welcome to the forums Violetta! Looking forward to your contributions. And you posed a very interesting question and have received many differing views.
Some thoughts that your post and some comments have inspired:
For many here in the West, Yoga is nothing but asana. Purely physical. And that’s fine if that’s all you want. There are studio’s that are run purely to make a profit and have no idea what the true meaning of Yoga is. Those studio’s cater to those who merely want exercise. There is a need and they fill it. Is this right? Perhaps for those students, at this time in their life, it is. But I like to think of it as a path to uncovering Yoga’s deeper meaning. Some will soon realize it after only a few classes. Others may take a bit longer, while others have no interest for whatever reason. I look at it as a way to pull them in.
I do see things changing in the West. I see more and more students hungry for Yoga. The asana’s become just a small slice of the whole. I see my students coming to class upwards of 30 minutes early to quiet the mind and meditate. We engage in meaningful conversations about living yoga. Taking it off the mat. When class ends, if they remain still and silent I know they’ve succeeded and as their teacher, so have I. But with all that being said, teachers need to make a living and studio’s need to make payroll and pay the bills. For what students get out of a yoga class, the cost is a mere donation. Yoga teachers will not get rich teaching, unless you are the likes of Rodney Yee, etc. Teachers plan, research and put a lot of time and effort into their classes. They should be compensated.
While the sense of community is a plus, I have found that is secondary to actual learning and discovering. (and not just the asana’s)
And finally, there is nothing natural about many of the asana’s. Asana practice is to get the body prepared for sitting in meditation for extended periods. Each body is different. Each body has different levels of flexibility. The reason for different or constant adjustments (verbal or physical) is not only to keep students safe, but to assist the student in going deeper when they are ready. This takes the keen eye of a good teacher. A home practice is as important as coming to class. They compliment each other. And from my perspective, there is no perfecting a pose. That should never be the goal. The goal is to be the pose. Feel it. Experience it. When we strive to “perfect” a pose, we are allowing ego to be our guide. A modified Trikonasana with a block or placing your hand on your shin instead of the floor is as appropriate as placing your hand on the floor. It all depends on your body structure, physical limitations and flexibility. In a good yoga class, you will see all students doing a beautiful Trikonasana, and each of them will look different in the pose.