Best practice to config ignore a message template text, but not the message view display etc?

Problem/Motivation

The "message_template" is a config entity type.
It is common that we want to export the definition of that entity type, and also the view display etc, to config/sync/, so that change will be synchronized on deploy.

At the same time, we may want to allow webmasters to customize the message text on production.
This will be difficult if we later override the value from config sync.

Currently we attempt to manage this with config_ignore, but we are not sure it is the best solution.
I open this issue to see how others do it.
Perhaps the replies can be useful to other site builders who want to solve the same problem.

Steps to reproduce

Proposed resolution

Describe the possibilities to exclude the message template text from config sync, but still sync the rest of the message template config entity.

Remaining tasks

User interface changes

API changes

Data model changes