Is that really geothermal, or is it a heat pump? A heat pump just uses the thermal mass of the earth to provide more efficient electric heating and cooling, it doesn't heat using geothermal power.
You're not wrong; however that is an unfortunate misnomer since ground source bore holes (along with horizontal soil collectors and lakebed collectors) on the order of 100-300 m deep are still utilizing heat from the sun stored in the ground, and not heat produced from Earth's core.
I'd say it's a pretty good idea to not conflate the two by using more precise language, even if not doing so might be "technically correct".
I installed a ground sourced heat pump a couple of years ago, and my heat pump manufacturer refers to it as geothermal: https://www.waterfurnace.com/switch . Most people don't think of this as 'geothermal' however so I avoid using the term.
It's a mix of geothermal energy (extra heat), and insulation/thermal mass abitrage. Several hundred tons of rock/stone/soil are a great insulator, and are going to be consistently above freezing, which means you get a munch higher starting temperature for heatpumps if the alternative is freezing air.
