This is coincidence, but it's too much coincidence not to have some merit.
Take a look at the 8 teams that made the division series. They were populated by a who's who of next-gen shortstops.
Astros - Correa
Dodgers - Seager
Yankees - Didi
Cubs - Russell
Nats - Turner
Red Sox - Bogaerts
Indians - Lindor
DBacks - Marte
Fine, Ketel Marte is the odd duck of the bunch, but 7/8 ain't bad (better odds than you'll ever get from Meatloaf).
Obviously SS was not the problem for the 2017 Reds. Zack Cozart had a career year, though injuries got in his way. The Reds failed for other reasons. Thing is, there's a strong possibility he's played his last game as a Red. Even if he hasn't, he's getting old for the position. The Reds are still rebuilding and we can see how young shortstops are impacting the game.
Unfortunately the Reds don't seem to have one of those in-house. Their nominal young SS would need to improve just to be replacement level. Jeter Downs had an encouraging season in rookie ball, but he's four years away if he's coming at all. Outside of that it's just good-glove, no-bat guys. So how do the Reds keep up with the Joneses? We're in an era that's starting to be shaped by these young shortstops. As someone who's baseball brain was forged around Davey Concepcion and Barry Larkin, I don't want the Reds to miss out.