In my book, the purpose of platforms is to deny an opponent access to a region of space. If the opponent happens to be there already, fine: they can kill the platforms or run away. There's absolutely nothing dishonorable or cheap about that. Sure, it's easy to get caught off guard by a platform rush, but that doesn't necessarily mean that platforms are broken.
I don't see why so many people don't like the fact that you can deploy platforms anywhere because they are "supposed" to be a "defensive" unit. Minlayers are "supposed" to be "defensive" units as well, so should we limit how close to an enemy ship they can lay mines? Should a defense field frigate not have any guns because it is a "defensive" unit?
For the sake of discussion, say you do impose a range limit on platforms. What should it be? What if you want to set a trap for an opponent between their resource op and their main base: do you have to move a carrier there first to do it? Do you have to wait to get a carrier to a resource patch before building platforms to defend your own resource op, or should you be able to send them there ahead of time? Once you set any type of range limit, you start limiting platforms in ways that I'm pretty sure the dev. team never intended.
This game is all about being creative and finding different ways of doing things. Having a certain pre-defined role doesn't necessarily exclude a unit from being able to do something else as well.
Am I telling people who disagree with me to stop complaining? No. I'm telling them to fully explore the game before they do. A well-informed complaint usually holds much more water than someone complaining after losing a game because their opponent suprised them with something unexpected.