I'm confused by your code, what is it supposed to demonstrate? perlunitut: Unicode in Perl warns against using is_utf8, so I wouldn't use it

Consider

$ perl -le " print chr hex q/C0/ " | od -tx1
0000000 c0 0d 0a
0000003
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when viewed as Windows-1252 it is À

And this

$ perl -le " binmode STDOUT , q/:utf8/; print chr hex q/C0/ " | od -tx
+1
0000000 c3 80 0d 0a
0000004
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when viewed as Windows-1252 it is À but viewed as UTF-8 it is 
And this

$ perl -MEncode -le " print decode(q/utf8/, chr hex q/C0/ )" | od -tx1
Wide character in print at -e line 1.
0000000 ef bf bd 0d 0a
0000005
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when viewed as Windows-1252 it is � but viewed as UTF-8 it is �

If you search for ef bf bd you'll see lots of questions about this erroneous conversion

So if you want to treat chr 192 (  perl -le " print  hex q/C0/ " ) as unicode you have to encode it, because characters 0 to 255 are also valid Latin-1, they are not utf8

$ perl -le " print chr hex q/C0/ " |od -tx1
0000000 c0 0d 0a
0000003

$ perl -le " print chr 255 " |od -tx1
0000000 ff 0d 0a
0000003

$ perl -le " print chr 256 " |od -tx1
Wide character in print at -e line 1.
0000000 c4 80 0d 0a
0000004
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Or, if you want chr 192 to return unicode, use encoding pragma ( utf8 pragma doesn't affect chr )

$ perl -le " use encoding q/utf8/; print chr 192 " |od -tx1
0000000 c3 80 0a
0000003
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