Based on our record, esp32 should be more popular than Helios4. It has been mentiond 3 times since March 2021. We are tracking product recommendations and mentions on various public social media platforms and blogs. They can help you identify which product is more popular and what people think of it.
Other SBC makers do have onboard SATA connectors but I've not seen enclosures like the EON. The Helios 4 is even bigger... Source: over 1 year ago
I have an original Helios4 4-bay NAS unit with 2GB ECC kit. I've used it on and off but I guess my needs have always been beyond what the unit can offer. Source: over 2 years ago
Esp32.net has a bunch of additional references, projects, and places to gather information. Source: over 2 years ago
Closest thing is the ESP32 from Espressif Systems See ESP32 link for details. Since you specifically asked for open source, so some tinkering and compile is required. Source: almost 3 years ago
There's also many more dev boards, chips and modules listed here, though they may not necessarily have platformio IDs. Source: almost 3 years ago
Intel NUC - Intel NUCs are available as Kits(Barebones), Boards(Mainbaord only) and as perconfigured Mini-PCs.
Intel NUC boards - Four-by-four inch Intel NUC boards come with a soldered-on processor.
ESPRESSObin - Electronics, Single Board Computer, and x86
SanCloud BeagleBone Enhanced WiFi 1G - One amongst SanCloud's range of BeagleBone Enhanced SBCs - each are enhancements of the BeagleBone Black (BBB).
UDOO BOLT - UDOO BOLT SUMMARY The UDOO BOLT is a quantum leap compared to current maker boards: a portable, breakthrough supercomputer that goes up to 3.
Olimex A64-OLinuXino - Open source hardware board that runs Linux and Android. Entirely designed with open source software CAD tools.