Actually, TS was riding a pretty high wave during the PMRC hearings. Their videos from
Stay Hungry were still in heavy MTV rotation and their songs were popular. What happened was the music industry caved in before Dee, Zappa, and John Denver gave fairly good testimony and pushed back against these Washington Wives in Sept 1985. Then TS put out a bad next album two months later, and their popularity waned significantly.
John Denver had several DUIs after the hearings and died in 1997. Interestingly, the PMRC etc also though Denver would testify in favor of their stance (he basically accused them of being Nazis). In contrast, Zappa toured in 1988 with a killer band (I saw him that tour) though that tour imploded in Europe due to personnel problems. Frank died more popular than ever.
