No, it's not true. I should remind you there was a lot of ERC20 asset that still defend its price caused by they have been creating a fully working product. that's the key to protect the investor's trust. I should remind you that it will have a correlation with the bitcoin price too. you can try to see the ethereum based icos which have created product.
Unfortunately, not all projects could develop to the level of which you speak, even having a finished product. A large part of them just squandered their potential, and all the money. Look at the volume of medium exchanges of similar projects.