I don't understand why anyone would sue. It only benefits the lawyers.
As I understood from the lawsue, it had been filled by the people who bought pre-sale tokens for 20 millions USD.
They hoped that token would significantly increase in price. Now they are angry that unlike many shitcoins (Dogdecoin, Ripple etc) WTT did not scyrocket, and want to get a compensation from GW. - but I doubt they will succeed.
The people did not sue GW because of the price issue, but because they bought their tokens during ICO sale in June - July 2017 and we are in January now and they still haven't received any tokens yet.
I myself bought 1.1k Giga Watt tokens in the 4th batch of ICO sale by transferring 5 ETH and I still have no idea when I will receive my tokens. They were supposed to be released in September.