Hard to see how them choosing to charge money to access their server will affect the future of the project, even them choosing to not run a free for anyone server any more wouldn't necessarily affect the future of the project because the project is not to provide a free for all server but to develop software. Either way, them trying to find a way to keep the server operating certainly doesn't mean 'Matrix is cooked'.

As far as Redis goes, as I understand it, they moved their software away from an open source license. There's zero indication Matrix are going to do the same thing.