One-way DB Migration Workflow

I’d like to understand how commonly a 3rd party installed/activated
plugins will make (structural) DB changes?

All the time for non bug fix releases. No matter what the plugin does, there are very few features that do not require some settings.

One way around this is to minimize the use of plugins.
The other way is to “intercept” the plugin’s requests to get the configuration from the DB and override it in your code. If foe example the plugin stores the relevant values in an option, IIRC you can use the pre_option_{option_name} filter.

You might need to add some plugin version check to return different versions of data between what is on production and dev.

To clarify, I do not expect I will be developing any of my own plugins or themes

Well, calling something 3rd party is not an excuse to not obtaining full control on what it does, as in the end you will need to solve any bug that happens on your site. Use only plugins which provide enough hooks so you will not have to run with them into a DB synchronization issues.