I actually like that better but I am thinking they might want to bring back those same actors in a few years for a continuation and didn't want to not have that option with the current actors and of course, they are doing all these spin offs with the adult actors anyways and that ending brings closure to the current show and cast.
Show runners said they didn’t want to show the future of some characters due to the spin-offs. Showings the kids as adults would limit what they could do regarding the kids and the spin-offs. I still think it would have been the best way to end the series, with that scene. But what do I know
The last few seasons of TWD have shown they are throwing stuff at the wall to see what sticks. What they say and what they mean have been wildly diverging concepts over the years. They're only interested in preserving that ambiguity so they can alter course again if the winds blow a different direction. There was never an interest in a satisfying end, because they want to keep milking it indefinitely.
