Indeed, just omitting binmode works; I can read both kinds of files on Windows.

Now another, related question comes to my mind. How about creating files? When I want to create on Windows a file, which has Unix line endings, should I then

• Pop the :crlf layer, or
• Explicitly set the :raw layer, or
• Just apply binmode without any layer

:) more options :)PerlIO::eol - PerlIO layer for normalizing line endings
Text::FixEOL - Canonicalizes text to a specified EOL/EOF convention, repairing any 'mixed' usages

Astonishing.

Well, now I have learned that explicitly setting the :unix layer is, depending on the situation, either evil or useless, I have to say that I indeed found a case where it seems to work in the way I originally intended: When it comes to creating a file, and we leave out the possibilities I mentioned, and the ones you added, and write it in the :unix layer way, i.e.

use strict;
use warnings;
open(my $fh,'>:unix','abc.txt') or die $!; 
print $fh "one line\n"
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we find that, after running this program on Windows, the line terminator of the file is LF (not CRLF). Different to reading a file, :unix layer seems to make sense here. Even unlinking the file works:

use strict;
use warnings;
open(my $fh,'>:unix','abc.txt') or die $!; 
print $fh "one line\n"
close $fh;
# No error message on unlink
unlink 'abc.txt' or die $!;
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However, this works only if we don't use binmode for setting the layer. The following fails:

use strict;
use warnings;
open(my $fh,'>','abc.txt') or die $!; 
binmode($fh,':unix');
print $fh "one line\n"
close $fh;
# Error message on unlink
unlink 'abc.txt' or die $!;
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This confirms the theory that the problem is not the setting of the :unix layer as such, nor the use of binmode for setting a layer, but the combination of both. Indeed, if we replace in the last example :unix by, say, :crlf or :raw, we don't get an error message.
-- 
Ronald Fischer <ynnor@mm.st>

print join ' ', 1, PerlIO::get_layers($fh), "\n";
binmode($fh, ':raw:perlio') or warn "UHOH $! \n$^E \n$@\n ";
print join ' ', 2, PerlIO::get_layers($fh), "\n";
binmode($fh, ':raw') or warn "UHOH $! \n$^E \n$@\n ";
print join ' ', 3, PerlIO::get_layers($fh), "\n";
binmode($fh, ':raw:raw:raw:raw') or warn "UHOH $! \n$^E \n$@\n ";
print join ' ', 4, PerlIO::get_layers($fh), "\n";
binmode($fh, ':raw:raw:raw:raw:unix:crlf') or warn "UHOH $! \n$^E \n$@
+\n ";
print join ' ', 5, PerlIO::get_layers($fh), "\n";
for(1..3){
    binmode($fh, ':raw:pop') or warn "UHOH $! \n$^E \n$@\n ";
    print join ' ', 6, PerlIO::get_layers($fh), "\n";
}
#~ binmode($fh, ':raw:crlf:perlio') or warn "UHOH $! \n$^E \n$@\n ";
binmode($fh, ':pop:pop:win32') or warn "UHOH $! \n$^E \n$@\n ";
print join ' ', 6, PerlIO::get_layers($fh), "\n";
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1 unix crlf
2 unix crlf perlio
3 unix crlf perlio
4 unix crlf perlio
5 unix crlf perlio unix crlf
6 unix crlf perlio unix
6 unix crlf perlio
6 unix crlf
6 win32
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if turning off unix and turning it on again, or turning it on twice, is wrong, perl should warn or die

PerlIO seems thin, OTOH, the test suite lists a TODO #56644: PerlIO resource leaks on open() and then :pop in :unix and :stdio but its closed

Any way you look at it there is nonsense around :)