This really isn't the right place for this, but I'll respond anyway.
The system allows for longer reviews. If the review window is small, you may not see what's there after the text scrolls up, but it's not erased. We have members who leave reviews that are a page long, so I know it can be done. I leave reviews that are one or two paragraphs myself.
As far as plagiarism, which is what you're talking about, it is illegal. ILLEGAL, not just immoral or unethical. People can, have, and will continue to go to jail, pay huge fines, and forever bear the stigma of being a thief and liar. No one likes a liar or a thief.
However, some ideas are common enough that they can't be considered the property of any one author. For example, a very common plot device is to have the main character kidnapped. That has been used by countless authors, and no one can claim that idea. But if your have your main character kidnapped by a spaceship piloted by small chartreuse creatures that speak Esperanto and live on a planet called Pfzbyzk, and someone else writes a story using those creatures, or that planet, then you might have a case to holler, "Plagiarist." That is purely an example, by the way, and not something that was actually written (as far as I know, and I deeply hope this is not taken as a prompt).