TL;DR: These scripts in the post use PnP.PowerShell to enumerate document libraries and compare file URLs against Search result to determine whether files are searchable. The plan was to show whether those files were indexable successfully, however the Get-PnPSearchCrawlLog is deprecated, see Deprecate Get-PnPSearchCrawlLog cmdlet for more details. This is because the underlying CSOM endpoint GetCrawledUrls has been deprecated. Use the first script when you want a quick list of files that are present in a library but do not appear in Search results.