>>dingo_+(OP)
I am afraid it is not so simple. There is a thing with data collector, and data controller in GDPR I don't full understand yet. It's not like you're not responsible for data collected by services that you hook up to your application.
>>dingo_+(OP)
You are the data controller because you decided that people who visit uour site would also load GA scripts. You decide what is done with their PII. GA is just a data processor.