Several other authors of software that accesses the Twitter API have come to that conclusion as well. When #Twidere, my phone app to access Twitter stopped accessing Twitter back in January I pretty much abandoned Twitter. I still check Twitter with its WebUI, less than once a week, but I no longer post or engage there.

But Twitter still gets used by some organizations I do work for, so I do post from their accounts. I wonder how long it will be before they abandon Twitter too.