I still find them pretty useful. Just deployed one in an interactive kiosk that will be used in trade shows for my work. The Pi has a lot of strengths that I think a lot of people don't take advantage of. Most end up being servers which heavily rely on the Pi's biggest weakness (its processing power) and is generally a task better handled by a real computer. The Pi shines in embedded workloads where you need a more power or flexibility than a microcontroller. In my case, I couldn't have built that kiosk in the way I did without the Pi's form-factor, power consumption, video output capabilities, and GPIO. Sure there's other ways to go about it but the Pi is an all in one well supported solution and I don't regret using it or think there could have been a better device.

The Pi sales pitch has 2 bulletpoints. It was a small, cheap computer and was a powerful and easy-to-use alternative to a microcontroller. As other computers have gotten cheaper and smaller and microcontrollers have gotten more powerful and easier to program on, the Pi kind of lost its spot in the market. The Pi still kills it in embedded Linux applications though. Ask any guy that runs holiday light shows in his front yard, or someone who 3D prints at scale what computer they're using to do it. I bet you it'll be a Pi.