It looks like Obsidian has a hard time indexing files that has hundreds/thousands of lines that are similar to this
E:\programs\Hexagon 2\Copia di Hexagon.exe (92 KB, 4/27/2006 12:46:22 PM)
I have couple md files that has historical records of folder structures like the one above, I printed them in txt files back then. It seems like Obsidian is getting stuck at these types of files when doing the intitial indexing. You need to have thousands of these lines in the files to experience the indexing issue.