Samsung Galaxy Buds immense RAM requirement
I think this is just a misunderstanding:

The Galaxy Buds don't need 1.5 GB RAM free (nor do they use 1.5 GB RAM). The requirement means that your Android device needs to have at least 1.5 GB RAM installed in total. How much is free at the moment is of no concern (this is managed by Android).

Therefore older devices and low-cost devices with 1.0 GB or even 512MB RAM are officially not supported. 

Your Galaxy S7 has 4GB RAM in total, hence you are fully compliant with the requirements.