Often it’s way cheaper to have one hardware version and control features in firmware, and that principle is even more true for silicon (same die but fuses that are blown to disable parts of it, or the chip clocked down because it might not perform properly at the speed of the more expensive SKU), so not surprising it’s this way!

I have confirmed this with my own version 1 SG108E (which additionally can't actually be managed without an ancient version of java and iptables /proc/sys/net/ipv4/ip_forward forwarding tricks. https://shred.zone/en/dev/setting-up-tp-link-tl-sg108e-with-...)

I'd say stay far away from this hardware line unless you actually do just want a dumb switch. If you do buy make sure you know exactly what hardware revision you're getting. I've heard the version 5 fixes it.