The ability to script out all linked servers can be done now using dbatools PowerShell module.

Copy-DbaLinkedServer will let you migrate the linked server to another instance, and will attempt to decrypt the password.

Get-DbaLinkedServer can be used to pull all the linked servers on a given instance, and then piped to Export-DbaScript. This used the same scripting method as SSMS so it will not pull the password out either.