You don't buy any plat do you ? Once you've spent your hard earned money on something and you don't get what you paid for, Then you will know why people complain.
Unless you are saying that many people do not get the platinum they bought, this doesn't make much sense. People get exactly what they pay for (platinum) and they can do what they wish with it. People complain that the chests aren't good enough and thts plat buyers are being ripped off...so what? It says that it is random on the item itself, people just ignore that and rage that they have used hundreds of chests and not gotten anything. Thats like people buying hundreds of lottery tickets and raging when they don't when. People are getting exactly what they pay for, they just sometimes don't like it.
As to the op, the reason they are releasing the new art is in anticipation of the new engine, which they have stated many, times is what they are focusing most of their attention on, in order for it to come out fast. As to not answering tickets, there isn't much to be said, except that they do their best, and its hard to read, check out, and fix each individual issue, especially with the limited amount of people on OTM's staff. Also, just be glad that there IS a support team, I have played a few games where the support is almost nonexistant, Several people I know have had answers to their tickets within few days, so it might just be you sent it at a bad time.
Not everyone is forced to buy plat, such as me, I have made it to lvl 170 without buying plat. Although people do need to buy plat in order to keep the market going, otherwise a lot of people will end up needing to buy plat due to the almost impossibility of lvling without elixirs whenever you hit 150+.
As to editing the ingame items, I admit that I was quite surprised that they actually changed the items that had previously been bought/rewarded, and I think that should not have been done, since many people spent a lot of gold to get them. But they were slightly overpowered, or at least the purple one for sure, especially seeing the new ones and how bad they are (compared to the previous ones).