In Magento 2 there is a table called
The table is created
What does this table do / hold?
Magento components uses this table as key-values storage for any data, if creation additional table is overhead. But many developers doesn't know about this functionality and uses
config or special custom tables for such data.
You can find all usages of this table using search among childs of
Moreover, this functionality available beginning from Magento 1.
Your module creates additional attribute set in InstallData, but you need to store attribute set id for usage in future.