I'm with you on the rant, but you may have mixed up a few things. Light itself is not curved, it can -be- curved when passing through a gravitational field, according to einstein's equivalence principle & special relativity.

If you place a bowling ball on a trampoline, then roll a marble in a straight line toward the bowling ball so that it passes by it to the left or right without hitting it, the marble ends up traveling an arc rather than straight line, due to the curvature of the dent in the trampoline caused by the "mass" (bowling ball). Same thing happens with light rays when passing through a gravitational field, they follow the curvature of the "dent" in space caused by a mass (example, the moon), except in space, the fabric of the "trampoline" is all around- and its called "spacetime" because space and time are understood to form a "fabric."

As for Einstein, most of his stuff still stands, some of it has been dis proven, and there's no consensus on the shape the universe (which would also assume it had one), so bottom line, light emitted by distant stars had to travel a certain distance to reach earth (measured by red shift), and didn't have the luxury of shortcuts or tricks along the way - the distance is the distance.

Whether or not we discover shortcuts in space travel some day is another question. One scary thing about astronomy and cosmology - the more you learn, the more you realize you don't know anything. It's no accident astronomers you see on TV have wiry hair, don't bathe and wear the same clothes every day- the study is all-consuming.