It is not the same anymore as it used to be, back in the day people did had younger peaks, but nowadays players do have older peaks, like having 30+ years old player is not that bad, people end up having 32-33 as their peak best years, back in the day it was 27 or so, and after 30 they were getting closer to retirement.
Look at the players who played during 90's for example, most of them retired before 35, and look at now, most players still play after 35 as well. This means that we need to realize that Suarez is still good enough, and I think it should be noted that he has been playing well right now as well, maybe he is not at his peak I can see that but he is still playing very well and still gets a lot of attention as well.
You are right, I do not agree that 25-27 is peak at all, I think somewhere around 30 is a lot more peak, and maybe a few years after that could stay at peak as well. This of course depends on how the player treats their body, but could you say Ronaldo had his peak at 25? I mean that dude was like a machine at 30, so I can easily say that he was peaking after 30+ without a doubt.
I agree that many people do end up with making some big progress later stages in their career, take care of their body and learn a lot about the game they play and become even better. We need to remember that physical attributes are just one part of the game, the talent and the wisdom are the other two and players gain both of them at later stages of their life.