The system requirements for this game are so high that there is no factory-made Amiga that could meet them.
The Amiga 4000/040 has a CPU at 25 MHz, not 40.
There was the late model 4000T/060 with a 68060 CPU at 50 MHz though (during the ESCOM years)
And the motherboard supported max 16 MB Fast RAM:
So, in other words, you would need some specific hardware upgrades, which very few people back in teh day had.
But today, perhaps an emulator, a Vampire (CPU in FPGA) or a PiStorm (ARM-chip that emulates the CPU) would work.
No, they are not high (note: I am the author of this Settlers 2 port to AmigaOS).
My port of RetroArch for AmigaOS requires at minimum a PiStorm CM4 equipped Amiga. THAT is high requirements. A 40 MHz 040 are LOW requirements.
25 MHz 040 is not enough to run Settlers 2 (we tried).
For most Amiga Users - even in the 1990s - "factory-made" was irrelevant. Especially as the factory-specs were always so behind.
"no factory-made Amiga" - that is exactly what we hated back then - that they only did Amiga games for "factory-made specifications". Our powerful hardware (of us Amiga users) was NEVER supported. No support for graphics boards, no support for PPC Boards... now I am doing Amiga games. Do you expect me to do the same mistake ? No.
And of course I am not doing it like "I target x". I port the game and then look "were can it run". Of course there is optimizations, and sometimes even doing "more minimal versions" (like the 320x256 version I added so that it can run on a 68040 and 50 MHz 68060). But what is your suggestion ? That the game should not have been ported because it does not run on some ultra-lowend setups nobody has anymore ?
Settlers 2 runs fantastic on a 100 MHz 060, a Vampire, a Pistorm, an AmigaOne x1000, in Lowres Mode even on a 40 MHz 040. This is for today's (small as it is) Amiga Market pretty lowend specs.
To compare:
Heretic 2 - AmigaOS 4 machine or PiStorm
Gorky 17 - AmigaOS 4 machine or PiStorm or 400+ MHz WarpOS Setup
RetroArch - AmigaOS 4 machine or PiStorm CM4 or 400+ MHz WarpOS Setup
The requirements of Settlers 2 are MUCH MUCH LOWER.
68020 was the lowend in 1995 or whatever. Today 68040 is lowend on Amiga.