Yes, immich is incredible! I have my entire family's photos (not all technical users mind you) synced and backed up thanks to immich server and its phone app. The web UI is easy, fast and they've even started adding basic editing capabilities recently.
I see a decent amount of skepticism and negativity in this thread, but I'm glad to see that someone is funding projects like this.
Even the previous-gen Pis would easily throttle under load without a heat sink (although usually installing a decent heat sink was enough to resolve the problem, assuming decent airflow). As the article notes, the heat was mainly from the SoC in the past. The Pi 4 is on a whole different level indeed.
I imagine the logic here is the same as with many other Pi accessories: if you need it, you'll buy it or get it as part of a bundle. In some cases throttling is not a huge issue. But we're a far cry from the simple plug-and-play Pis of the past... Another issue is power -- you can't simply run the newer Pis reliably off any old cell phone charger you have laying around.
I see a decent amount of skepticism and negativity in this thread, but I'm glad to see that someone is funding projects like this.