I have just started reviewing what's available in the ArcGIS Pro SDK for creating datasets and making geodatabase schema changes (e.g. creating feature classes, relationship classes, adding fields etc). It seems like the ONLY way in the Pro SDK to perform DDL operations, like creating a feature class, is via GeoProcessing tools.
Running GeoProcessing tools is fine for only the very basic scenarios, but if we want to create a feature class in code with a large number of fields, it is a) messy from a code perspective, b) gives a poor user experience and c) results in poor performance (as can be seen when attempting to add many fields manually in ArcGIS Pro).
DDL operations like these could be done easily in ArcObjects and DDL operations should also be possible in the Pro SDK, without having to run geoprocessing tools.