Tron a scam? Do you mean you lost money buying at the top? So many people are quick to call something a scam just because of their own misjudgment/timing. I think Tron is a solid project and will come through soon!!
No, I don't think that the OP was referring to the trading mechanics. Obviously anyone who's an overhyped coin and then saw it being dumped all over the place would be furious.
He's taking a hit on the main guy behind the coin. For instance, you can talk about Vitalik Buterin and discuss his personality. You can clearly see that he's leading Ethereum in a good manner, which helps Ethereum sustain in these markets conditions and, imho, will help it whether the turbulence down the road.
With Tron, there's a lot of articles online about the scam roots of the leadership. So, it can easily actually be one big scam. And I do believe that it is not difficult to engage the bots to trade your cryptocurrency. The expenses you incur in doing that are completely rational, if you own a large chunk of Tron. You just to wait until the vaporware has been seens by the majority of traders and sell your holding at the top, leaving those great guys that wanted to hodl you to the Moon to hold the bag...