An ESP32 (and oh man they’re great) is more powerful than a mid-late 90s desktop, but power isn’t what separates a computer from a microcontroller. It’s the abstraction compared to the bare metal control.
(To be clear, the project in the post is very much embedded, but programs running on a vm written in a high level interpreted(ish) language are not so much.)
embedded is a term that means your code is closer to the discrete component analogy as possible, with all the same design and testing expected from the electrical design.
If you want to add modern language niceties to it, fine, But I would say that anything that brings in the "app" concept, and specially installation and fleet management, the better term is microcontrollers.
And there are perfectly fine open source solutions with the same goals, such as https://archive.fosdem.org/2020/schedule/event/ioterlang/
A watchdog timer is often a piece of functionality internal to an MCU. https://microchipdeveloper.com/8bit:wdt The majority of embedded development does use watchdog timers, at many levels.
Java is running inside of this card, https://zdcard2.en.alibaba.com/product/60655706921-801652433...
Maybe the industry would benefit from some more fine grained terminology here, perhaps call the small stuff MCU embedded?
But that's not the important part. I think one major problem is that the term "embedded" puts a lot of engineers into a frame of mind that rejects programming in anything high-level. We have done lots of projects where something like MicroPython would have been perfect, but every time I try to sell something like that, I get a bunch of excuses that really aren't grounded in any concrete objection and we go right back to twiddling bits in C.
Then every time there's advancements in what you have available, people add all the niceties back. And at this point it is not embedded anymore. It's just a low power full device. Just like java for the MSP430 (like anyone would spend $7.99 per chip for a TV remote with 2week batteries, instead of $0.004 and 2+month)
True embedded development usually doesn't even have room for a watchdog timer. let alone virtualization and memory protection.
This is not new. This is not embedded. This is just the usual cycle of hardware generation changing and people in academia ivory tower (or worse, google solid gold tower) having nicer toys than everyone else.