I think you should upgrade your server as much as possible as long as it is compatible with the scripts you run.
You don't want to be stranded with a EOL application.
I had one large site on a dedicated server the owner turned off upgrades years ago.
It was so long a duration there was no tool to upgrade anymore.
So it became easier to just migrate to a new host.

In fact site one php is getting old in the tooth so when I have time I will upgrade .