Oh boy .... vendetta? You really don't know if you say that EIA-232 is "low-impedance" when all the datasheets say "300 ohm" output resistance. That is never "low impedance".
The original 232 standard offered noise immunity, albeit at very low speeds (20kbps max although 250kps is still slow) over relatively short (50 feet max) unbalanced lines but that is the point. Even if properly adhered to with a +/-3V receiver sensitivity the standard is sadly lacking but worse still, receivers do not have anywhere near this level of "noise immunity" with only a few hundred millivolts of a noise band centred around +1.5V or so. That's because it is a simple transistor input stage with very limited hysteresis.
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Drive that long cable instead with 0-5V into a CMOS receiver with a termination resistance and you will find that it can run at higher speeds etc. One of my early designs were R6511AQ based POS terminals and before I started using RS-485 for multidrop, I used a simple PNP driving a multidrop line from +5V for hundreds of meters over standard 4-core data cable. They just worked although RS-485 allowed much higher speeds and more immunity to noise.
I put MAX chips in decades of commercial product so obviously I do what I need to do, and don't do what I don't need to do. Do the science, do the math, connect the chips up to the scope and meters etc and vary those input voltages which will confirm exactly what I have said.
I've said what I've said for hobbyists overly concerned with meeting the RS-232 standard by using any brand of special RS-232 chips when the simple boring truth is you don't need to.