I am using perl 5.28, but I get the log getting written after sleep completes, I tried different timegap

PS C:\Users\VinothG> perl -E"$|=1;print $];sleep 10" >.\tmp.log
PS C:\Users\VinothG> cat .\tmp.log
5.028001
PS C:\Users\VinothG> perl -E"$|=1;print $];sleep 20" >.\tmp.log
PS C:\Users\VinothG> cat .\tmp.log
5.028001
PS C:\Users\VinothG> perl -E"$|=1;print $];sleep 30" >.\tmp.log
PS C:\Users\VinothG> cat .\tmp.log
5.028001
PS C:\Users\VinothG> perl -E"$|=1;print $];sleep 40" >.\tmp.log
PS C:\Users\VinothG> cat .\tmp.log
5.028001
PS C:\Users\VinothG> perl -E"$|=1;print $];sleep 100" >.\tmp.log
PS C:\Users\VinothG> cat .\tmp.log
5.028001
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My PowerShell Version

PS C:\Users\VinothG> Get-Host | Select-Object Version

Version
-------
5.1.18362.1474
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