The situations are different. When a version of PHP is obsoleted, the upgrade in the source code is minimal. Or we could just upgrade the PHP and see if the site works or not. If not we can upgrade the code or we could just isolate the site in a separate cPanel account with old working PHP version. No sweating!The same could be said for any piece of software. We frequently retire PHP versions as the distributor stops maintaining them and they become obsolete, and the same thing happens with the operating systems.
That is why cPanel should talk with them or support the users or find the best way for smooth transition.If ELevate isn't an option for you, a traditional migration using the Transfer Tool is the best way to move the data, but this seems like more of a limitation from your host than from any cPanel tools.