It's not surprising that they have taken off like they have. Initially it was because it was inexpensive, but now the community is huge and that is a very attractive selling point.
You've also got the nRF52 USB dongle which seems similar to those cheaper ESP32 kits, for around $10.
> and going past that requires a JTAG programmer
No, the official Nordic devkits comes with a built-in debugger. Same for micro:bit. It's just plain USB.
That said, I do think Nordic could be better at penetrating the hobbyist/student market. I think one problem is the lack of a combined BT/WiFi chip.
I think once Zephyr becomes more mature and there's more tutorials/guides around it, a good BT+Thread+WiFi solution from Nordic could become very popular. Zephyr is a bit hard to get into, but incredibly powerful once you get used to it.
Right, the devkits can do this. If you want to go past that, like making your own PCB with a NRF52 on it you need JTAG, which is not a requirement for esp32.
Maybe the NRF52 has some sort of ROM serial loader that I've missed though.
Segger has been really successful at marketing "JTAG == JLink" but it is just not true.
[1] https://www.seeedstudio.com/Seeed-XIAO-BLE-nRF52840-p-5201.h...
Out of curiosity, how do you flash the nrf52832 board?
[1] https://www.tag-connect.com/product/tc2030-ctx-nl-6-pin-no-l...