AMC1303M2520: Delta-Sigma modulator with clock output would fewer and fewer

Tool/software:

I wonder why there are fewer and fewer of Delta-Sigma modulator with a clock output pin. The TI's contact window told me that the Delta-Sigma modulator with clock output would be fewer and fewer and suggested me to use AMC1306 that is a Delta-Sigma modulator with clock input. Nowadays, I'm using AMC1303M2520 in a mass production project.