Idk where outside the USA you are, but the IBM PC easily had the easiest time taking over the USA. Amiga and Atari were considered hobbyist computers while Macintosh constantly battled DOS until slowly fading to irrelevancy between Windows 3.1 and Windows 95, not regaining real steam until Mac OS X 10.2-10.4.
The TI series was very common on the super low-end/hobbyist end, and Sinclair/Coco/Dendy/Timex/etc derivatives had negligible marketshare.
In Brazil we had mostly Sinclair, Apple II and TRS-80 (Model III and CoCo) clones and compatibles. PC clones were very expensive and only appeared later - and only became popular through smugglers, about the same time MSX 1.0 was introduced. I believe there was only one MSX 2 machine that was actually sold. Brands like Atari, Commodore and Apple were extremely rare. This was all because the military dictatorship reasoned, somewhat correctly, that in order to grow an indigenous industry, it'd need to prevent imports of small computers and heavily tax other segments.
The Sinclair and TRS-80 clones arrived in 1981, the Apple II in 1982 and the PC XT in 1983 (at the absurd cost of US$15K for a configuration that would be US$5K in the US. This dropped to around US$3K by late 1984 for a configuration of similar price as the US, so not the "many times more expensive" that most people remember). There were very few TRS Color Computer clones, a single Sinclair Spectrum and the single Macintosh clone was not never authorized (every computer launch had to be approved by the government). The two MSX officially arrived in 1985 but sales actually started in 1986. The PC AT clones only started selling in 1987 and 386 machines in 1989 - these were the longest delays of all. An even longer delay was in PC graphics, which were stuck at CGA from 1983 all the way to 1992 (with imports allowed there was a jump to VGA+Multisync).
With the exception of the Spectrum and Mac clones by companies that had invested heavily in their predecessors, nobody tried to copy machines with custom chips, so no Ataris, Commodore 64s, Amigas, etc. The Commodore Pet would have been easy to clone, but there was no preexisting market of contraband machines due to the awkwardness of lugging the built-in monitor.
After the reserved policy ended in 1991 a company called PCI do Amazonas brought the Amiga to Brazil and was officially still making the A1200 months after Commodore itself had shut down. So we did get one of the three 68000 machines, even if very late.
almost everyone and most companies bought grey market "imports from Paraguay". which were 1.5~3x the usa price for pc.
also there were two prominent cpu fabs (churning 8080 and 68k) that the usa managed to close, further digging there interval market into cheap clone territory with that joke that was the apple ii clone announcement in a fountain.
That still felt like a downgrade from that Atari ST in many aspects. Usability? DOS? Early Windows? Unix clones? UGH!
Sure, it had some oomph, but the ride wasn't smooth.
the pc were the best thing one could get that was not a commodore or a bootlegged import chiclet keyboard from the uk.
the amigas were considered just expensive game machines. the apples were an extremely expensive status symbol, and the you felt like a fool because there was no compatible peripheral anywhere.
and the Ataris were unheard of.