I think you are confusing irrationality with ex-post regret. It is to be expected that people would come to regret many choices that were rational at the time t

I think you are confusing irrationality with ex-post regret. It is to be expected that people would come to regret many choices that were rational at the time they were made. Not everything we do is rational, but all the things you mentioned can -- and imo should, absent evidence to the contrary -- be treated as rational choice.