With UA it is possible to declare a variable of type 'Google Analytics Settings' and in this variable we can set the GA container ID + all fields we want to set + all custom dimensions we want to set. This allow us to do this configuration only once, and then any tag that uses this configuration always sets these global fields and dimensions. This is for example useful for pushing the user ID.
With GA4 this variable type doesn't seem to be supported. We are only allowed to use Tags and on each Tag the GA4 container ID needs to be set individually as well as all the fields and custom dimensions. This means that for every tag that we have we need to remember to set all fields and dimensions each time.
I have over 100 Tags in GTM that I am converting to GA4 and this is becoming a real pain. I can already see the issues with maintanance as there is no single source for this configuration and if I later decide I want to add a new custom dimension I will have to add it to all 100 fields, where in UA I could have justed edited the variable and it affected all the 100 tags automatically.
Am I missing something? Is there any way to set global custom dimensions and fields in GTM when working with GA4 container?
UA variable configuration allowing for global fields and dimensions:

GA4 tag configuration requiring individual fields config per tag

