These arguments can only be answered in retrospect if you were really *IN* to computers when the 8-bit to 16-bit crossover occured in your country (or "territory" as the media pundits would have it.)
People who were *IN* to computers tended to be the younger user who were normally dependent on someone else to fund the purchase of a computer. Ideally, for Christmas. Or maybe a birthday. Or a special present, or something like that.
The ST/Amiga wars only came about because of BAD DECISIONS and once the computer of choice was purchased, THAT WAS IT. You HAD to defend your choice. You CONVINCED yourself that your decision was RIGHT.
Let's face it...
Many Commodore 64 users bought an Atari ST in a hurry for two reasons: 1) they were really *IN* to computers and there was a lovely new 16-bit machine available that was affordable and 2) it was released before the Amiga had hit their (or parents') price bracket.
Right? Any arguments there?
Once it was acknowledged that the Amiga outperformed the ST in terms of specs, former Commodore 64 and ZX Spectrum/Amstrad/Schneider/MSX/Atari 8-bit/whatever users decided to buy an Atari ST for THREE further reasons: 1) it was STILL cheaper than an Amiga, 2) it had more software than an Amiga and (most importantly) 3) they had friends who already owned Atari STs and could PIRATE software from them.
During 1988 it became obvious through demos, games software, utility software, advocacy through magazines and usergroups, sound demonstrations, availability of PD software, media hype, levels of piracy (sad but TRUE although the ST had a nasty UK piracy following) that the Amiga was fast overtaking the ST.
In 1990, every single fact you can point to - sales, specs, support, users, availability of PIRATE software, you name it - proved that the Amiga was superior to the ST in EVERY SINGLE WAY with ONE exception....
...the inclusion of a MIDI port.
Nothing more, nothing less.
A MIDI port that would've cost around thirty UK pounds to add to an Amiga and with better software (Music X, Bars & Pipes, even Octamed!)
It's a grossly overlooked fact but PIRACY very often drives the take-up of new machines, and with an established userbase of ST owners, others jumped on board safe in the knowledge that, following a 300 quid outlay, they could secure new software for free. Once the Amiga scene was rampant, more and more users jumped on board the SUPERIOR machine when they could afford it.
Don't get me wrong; I *loved* my ST when it was the only 16-bit machine I had ever seen (the music on Goldrunner! The playability of Super Sprint! The cartoonish realism of Road Runner!) but when I saw an Amiga my jaw hit the floor and I was hooked. The ST looked like a Speak 'n' Spell.
Just some personal feelings..... hope I haven't bored anyone!