simply because it had bad or "out there" show finale? I mean, you seemingly hardly see it in reruns any more, and you never hear it talked about in big streaming deals, even though at its height, it was one of the biggest shows on TV at the time of it's ending.

In the case for HIMYM, the final episode basically made the previous nine seasons pointless in it's last five minutes. It also made the Mother seem like a consolation prize as Ted had always been pining after Robin.