Note that you can circumvent the PATH_MAX limit by using UNC filenames, as discussed in the CreateFile documentation by Microsoft. Some short testing shows that not changing the directory seems to work:

perl -MFile::Find -le "for $d (@ARGV) {print qq(Scanning $d);find({no_
+chdir=>1, wanted=>sub{print $File::Find::name}},$d)}" \\?\Q:\ Q:\
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Without the no_chdir option, scanning the first entry (\\?\Q:\) fails immediately.