2. no gaurantees???? 3 words friend, redhat package manager, RPM. It WILL NOT ALLOW YOU to break software by installing or upgrading.
Really? If I switch from Redhat 8 to Redhat 9, my application will work EXACTLY the same, without a recompile?
Can I take a Linux application written 10 years ago, and run the compiled executable on the latest Fedora?
RPM has little/nothing to do with this.