Warming up before singing can help improve vocal performance, especially if it helps to reinforce the good habits of good vocal technique. The muscles within the larynx have functions for pitch control and vocal fold (cord) adduction, so that it is done in a safe way. Using those in the warmup can be beneficial, to prepare for singing.
The muscles connected to the larynx, such as the hyoglossus, the sterno-thyroid, and sterno-hyoid, are helpful in preventing excessive laryngeal elevation, the usual cause of strain when singing. A balance, so to speak, between so-called high larynx muscles and low larynx muscles can help to keep the larynx in a stable position, ensuring a smooth tone and one without register transition issues (cracks, breaks, or a “disconnected sound”). Warming up with a stable larynx, not too high or too low, helps to prepare for singing the same way, resulting in a performance without strain or endurance issues.
Warming up without target-specific exercises or vocalises, is probably not going to help with a performance.