Yes, there is a clear difference between regular AC servicing and deep jet cleaning.
Regular AC servicing means checking cleanage of the basic filter, light coil washing, drain cleaning, checking gas pressure, and performance testing. This helps the AC's cooling performance.
Deep AC jet cleaning is a more upgraded process, also called power jet cleaning. High-pressure water is used as a jet and other specialized equipment to thoroughly remove dirt, grease, and mold from the indoor unit, cooling coils, blower, and drain pipe.
If you see that your AC has serious issues, like it is emitting bad odors, leaking water, or not cooling properly, then deep jet cleaning is the best option to improve the performance of your AC.