Hi,
Three years ago Wordpress incorporated responsive images in its core (scrset image-set). Theme X disabled it and has since then not made any progress on incorporating in the theme (at least not that we know off). All I read in previous posts is promisses about the team working on it. For years already.
Serving images that are too large for mobile devices is becoming a big problem in the digital world that is focussing more and more on imagery. Wordpress has solved that three years ago, after meticulous developing and testing. To be honest, I think it is outrageous that Themeco has been giving it so little priority in the past three years, and on top of that keeps their customers completely in the mist that whole time regarding an ETA.
This attitude is starting to become a true deal braker for me. I own about 10 licences now, but I cannot convince any new customers to buy a theme for wordpress where its developers so blatantly ignore this essential part of Wordpress, the open source software that is the (lucrative) core of your business.
Please be open about your plans, and provide us with an ETA.
Cheers