A lot, of late.
Yoga research is sometimes a revelation and sometimes repetitive, as with other medical research.
But a lot of what is done under the name of yoga is also done in different contexts. Exercise, mindfulness, positive emotions, and good breathing, for example.
Much of what is done under the label of yoga therapy is non-controversial. Often because some form of it is already being done in rehab, movement therapies, psychological interventions etc.
Fact is, going from doing nothing about your health problems to doing something about your health problems is itself helpful.
Talking to someone (maybe your yoga teacher!) is helpful.
Taking some good deeps breaths a day is helpful.
Appreciating that you’re alive and have something to do today is helpful.
Being present in the small moments of the day is helpful.
These are all researched in some context. Nothing particularly esoteric or mysterious.
We can do all of these in a yoga session.
The point is that a lot of yoga therapy is non-controversial. We may not have hard evidence for specific protocols, but a great deal of healthcare is like that. A lot of yoga therapy on general terms, rather than the specifics of any protocol, is quite sensible and can be expected to work.
After all, what is so surprising that moving, breathing, and being present is helpful to health? Yoga delivers that in an excellent holistic framework that can integrate with many other modalities.