Did Joe Walsh ruin the Eagles?

Say what you want about the Eagles, but they are the most commercially successful American band of all-time.

I was watching the History of the Eagles on Netflix the other night and learned a lot about a band that has only released one full-length album during my lifetime. It showed the different phases of the group as they transformed from country rock to arena rock over the course of the '70s.

Glen Frey was constantly trying to take the band in a more rock-oriented direction, while Bernie Leadon wanted the band to focus more on their country roots. Even the band's first producer Glyn Johns, who worked with Led Zeppelin, The Rolling Stones, Faces, and The Who, said the band didn't have what it takes to pull off the "rockin" sound.

Don Felder was added to the Eagles prior to the recording of On the Border in order to further emphasize the rock elements of their music.

However, most critics and musicians seem to attribute Joe Walsh's arrival as the Eagles watershed moment (either good or bad depending on your opinion).

So what does the board think? Did Walsh ruin the Eagles and aid in their mainstream success, thus further deviating from the Laurel Canyon/LA country rock scene of the late '60s and early '70s? Or did he provide the band with a new dynamic which allowed them to transcend genres?