I found an interesting article that expounds on this topic: " Is the modern-day TE position at its evolutionary crossroads?" [
www.profootballweekly.com]
Among the points made therein:
"The dual nature of the TE position is what makes it unique. Teams had the luxury of carrying multiple tight ends on the roster, each with the ability to block and catch at the requisite level. Now, those roles have been divided more often that not with one tight end focused on the in-line, more physical nature of the position, the other on the more evolved, pass-catching area."
...
"If teams can counter the evolution at tight end with their own chess pieces, when will the time come when offenses simply replace those tight ends with quicker receivers more adept at route running if they are going to pass anyway? Perhaps sooner than we think."
...
"It’s an amazing thing to see players like Gronkowski, Ertz and Kelce play tight end the way they do. But it’s also important to remember they are unicorns, exceptions to the rule not easily found and not the template for which teams should be searching long and hard for."
AlbaNY_Ram