I think glob and readline are great at specifying exactly what you are doing, and both are resistant to casual errors, especially when your glob and filehandle can look so close:

my $line = <$fh>;  # Filehandle?
my $file = <*fs>;  # Glob?
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Much better to be specific, like you say:

my $line   = $fh->readline();  # Filehandle!
my ($file) = glob("*fs");        # Glob!
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The angle brackets and the whole DWIM thing are for "programmer efficiency" and not necessarily "program clarity". In some cases, you would want to avoid them entirely.