This has been common in Sweden for decades, I had it in my previous house almost 20 years ago. If I remember correctly it was a 100m borehole. The only limitation is that certain soil/rock environments work better than others, so it’s not suitable for all locations.
Heated our house in northen Sweden just fine in -20/30C winters.
For Christmas my partner wanted me to write down my vows to them. So I bought some quality paper, and made a fancy card. On the front I wrote “I vow to…” then on opening it there was a big picture of Rick Astley and lots of lines scattered about such as “🎵 never gonna give you up…🎵” etc. etc
On the facing page I did write something serious and heartfelt, but the rick rolling was necessary.