I know it has been a huge pain in the ass for some applications that use older ODBC drivers when Azure made TLS 1.2 the default for Azure SQL databases.
I don't want to know what other security holes exist in applications that don't even support TLS 1.2.
Sometimes it's the OS that is obsolete: modern versions of Chrome (from questionable sources) can run just fine in Windows XP, but any application that depends on the OS for its TLS support will be greatly disappointed that XP is now effectively locked out of modern crypto due to lack of updates.