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I don't think the 80-character limit in PEP-8 is doing many people a great deal of harm.
FWIW, I posted two recurring examples of where it is awkward in normal python programming. One, raising exceptions with messages -- the message doesn't typically start until 30th column or so. Two, in unittests using self.assertRaises(SomeException, expr), the expr part doesn't typically start until the 35th column or so. Also, there is a problem with indented multiline string literals where the indentation is taking up space that will never be shown to the end-user. Indented comments and in-line comments are also space challenged.
I think the Google example is instructive. Their two space tabs are not a natural preference for anyone I know. Instead, it is an accommodation born from trying to fit nested, indented code into 80 columns. I'm pretty much in agreement with the OP that going to 90 or 100 columns is a better solution.
Of course, if Hollerith punch cards come back into vogue, then the OP's proposal won't work out so well ;-)