He was in several bad films, but *Lone Star* off sets most of that. Nothing will ever justify his work with Jane Fonda in *Rollover*, a truly bad film (though to be fair I spent most of it making out with my then college GF in one of the back rows, so no complaints from me. A good film and performance would have been a problem for me).
He wrote some very good songs. I agree with him that others sang them better than he did, though partly that is because of the quality of those others. And his time on stage with the Highwaymen still delivers goosebumps. Not a bad career at all.