What you are describing is the SmartThings architecture, and I would not expect it to change any time soon, if ever. The ST Mobile App always connects to the ST Cloud, which in turn connects to your ST Hub. All automations, except “SmartLighting”, run in the ST Cloud.
If local processing and connectivity are important to you, you may want to consider alternative home automation solutions to augment ST. Apple HomeKit, Hubitat, and Home Assistant all support local processing and connectivity without an internet connection required at all times. For things like voice control (Alexa, Siri, Google Home) an internet connection is required to process your voice into actions.