19.07 was the last version that supported 4/32 operation (and really it couldn't run properly), and we're now several years past that. Even with 19.07, you can really only fit OpenWrt if you remove thinkgs like LuCI and the opkg package manager itself.... you might even have to remove critical features like the firewall if there was anything else you wanted to isntall. So no, even with the most minimal distribution, you'd be hard pressed to be able to install anything else.
It is extremely unlikely that anybody would spend time to add OpenWrt support for such a low spec device given that 4/32 devices are officially unsupported and it would be effectively impossible to fit with the linux kernel as it is now (and support would never be added retroactively).
Of course, you could certainly try to get it running, if you want.
If a minimal dist start the system and access network, then you can load all the extra packages of a full openwrt dist (like luci) in each boot from network (like a own remote http server) to RAM.
So a 4MB device can enjoy fully all the features of a standard openwrt dist. This device has 64 MB RAM.
This device is only behind minimal specs in flash memory, it has enough RAM and enough processor to run modern openwrt versions. And you dont need a big flash memory if you have permanent internet connection to download all you need.
I dunno man. In isolation 7usd is nothing, but from a dodgy noname brand without verified Openwrt support and only 4MB flash you might as well treat yourself to a cheeseburger instead.
On the used marked you get like "proper" repeater devices from proper brands, and with openwrt support for 5-10usd. The reason is that wifi speeds (on paper at least) have have really accelerated the last years. Also 2,5 and 10Gbit ethernet is becoming more and more mainstream. Fact is that most of us are still on Wifi 5, while Wifi 7 is about to launch. So even good AC1200-1900 repeaters are almost given away since they are seen are "useless".
64 MB RAM and 600 MHz is in this cheap device. The same than some current officially supported last versions OpenWRT devices.
One decade ago kamikaze worked fine in AR2315 SoC with 180 Mhz and 16 MB RAM. And of course, more expensive routers in that date, well, it was another age, and another speeds, but for some applications is still useful.
You're not giving useful information, I dont understand what are you doing in this thread, maybe it's you who want to promote/sell expensive routers, who knows. But I can swear to you, I'm not a Aliexpress vendor .
Looks like you are convinced that you found a nice device at a great price, and nobody is going to be able to change your mind. I guess it's time to move on and enjoy your device. Please, keep us informed of your advances.