@gianluigi @snicho – this kind of conversation is why I love the developer’s community!! 
Yes, generally speaking column IDs are just placeholders to ensure we can reference each column in a unique way. The item name is always stored in a column called “name” as well.
If you need to keep track of your column IDs despite changing names, I’d suggest using the columns object on each board to keep track of which title corresponds to which ID. This is the approach I’ve used with some of my code as well 
Let me know if that makes sense! 
Dipro