The phrase "rosy projections" refers to positive and optimistic predictions or expectations about a certain situation or outcome. It suggests that someone is envisioning a future that is very hopeful and promising. Full definition
Republicans, who managed to pass a $ 1.5 trillion tax break at the end of last year based on unrealistically rosy projections of outsize economic growth, are now seeing their president take actions that economists say could undermine that very same economic expansion. (vox.com)