Snap your fingers if you think Joe Walsh ruined the Eagles or Michael MacDonald ruined the Doobie Brothers

Your examples are poor. Those you listed were actually quite good.

If you want examples of terrible replacements, then look no further than Ripper Owens and Blaze Bayley.

Michael MacDonald definitely ruined the Doobie Brothers. Can't stand his voice.

Most musicians are like hookers and do anything for the money.

I actually like Joe Walsh‘s song ‘Life’s been good’ ..

And Joe Walsh did Hotel California.. cmon that’s a good song, one of their best.

Oh please. Even Elton John never made that mistake

They became session players after that. It was Michael MacDonald and the Doobies. They may as well gone to 100% recording TV sitcom theme songs.

And Walsh's old band that he dumped? Cest la vie.

One day you're in a band with Joe Walsh, with a hit record, the next he's joining the Eagles onstage to perform Rocky Mountain Way as an encore... For their Eagles show.

I agree about the Doobie Brothers, after Michael MacDonald joined their music was no longer any good, it became lame and I really didn't like his voice to begin with. They became more commercially popular after he joined though.

As far as Eagles I never did like them. Hotel California was played so often for so many years on the radio and I hated that song to begin with. None of their music ever appealed to me though.

The style of music changed for the DB with McDonald. They had their most success with him but going from China Groove to What a fool believes is a major change for fans. McDonald went on to a solo career that worked out for him too.
I think many bands change direction or lose chemistry based on influences on band breakups especially when the lead vocalist is changed. Journey has never had a real hit after Steve Perry left.