AllTimeMarr, you dont need to use $null to replace it
you can use simply

alias htmlfree { return $regsubex($1-,/(^[^<]*>|<[^>]*>|<[^>]*$)|&[^;]+;|/g,) }

in fact the $htmlfree can be just

return $regsubex($1-,/<[^>]+>/g,)

or use

return $regsubex($1-,/<[^>]+>|\t/g,)

to replace tab too