You know what? I think you might have answered a different question, "Why do I associate Harrison Ford's character's misery with Harrison Ford's misery as an actor?'"And he has that same air in press junkets, so I guess I naturally make the connection to "this man, Harrison Ford, does not want to be in front of a camera."
I checked on Dreyfus' filmography and I think I was hallucinating. He doesn't have a descent-into-madness in the wild, unless you cound What About Bob?
Ford's character in graffitti seemed predatory to me, probably because he was a man in his twenties getting high school girls in his car... maybe something not entirely foreign to Ford if the stories about him and Carrie FIsher are true. Not to mention Indiana Jones sleeping with teenagers.
I'm not French, and thanks for reminding me of that because I just made the error of writing mon freres instead of mes freres and you reminded me to correct it... I dabble in French but haven't done a deep dive. And speaking of pedophilia (or hebephilia, if you are so inclined), I think French were pretty horrified by Luc Besson take in Leon because it was Jean Reno himself pushing back against it.
As for whether Ford really does dislike roles, I know he's pretty open about not liking Star Wars and just made the connection that he's a guy that'll take a paycheck. I don't think I've seen him actively diss other roles he's taken.