It follows the Upgrade Path as it involve changes around DB tables and also functionality around ECAD and others. This path needs a change in different areas too like:
2-Creo
3-Creo Adapters
4-WGM installers for users
5-JRE update
6-CAD worker setup.
So rolling out 10.2 needs others areas to do impact analysis/risk assesment in your company or for your client.
The major fixes around other functinality may have set the PTC to put it under Upgrade Path.