People aren't taking this seriously because in this case they disagree with Eich's opinion, so they feel it's all okay. They're letting that blind them.
What if Eich actually had the "right" opinion? And this is hypothetical at this point--I'm not talking about gay rights anymore. Suppose you are an oracle and you know that the mob was wrong rather than right and Eich was right rather than wrong. Don't fool yourself into thinking that things would be different. They wouldn't, and this has caused extraordinary difficulty in righting many wrongs of the past, including slavery. It can severely impede the democratic process because people are afraid to hold dissenting opinions--not due to legal ramifications, but social ones.