Considering how many interesting issues that specific CentOS7-locked job had just with updating kernel to latest LTS (which required a lot of fun stuff as well, given that it didn't compile with included GCC)...
... I can imagine.
... I can imagine.
The problem is, scientific software can silently error out in many ways (like slightly lost accuracy), and detecting and fixing those will take some time.
Considering some of these tools are developed over (almost two) decades, there's a lot of verification we have to go through.