It's interesting, I split my childhood between Hungary and South Africa, and pretty much along the timeline of the 486. During the late 80s in Hungary, the Amiga certainly was a big thing, even in schools. I suspect it was due to the price; even an Amiga was considered super expensive, and if you ran into a PC it was either at your parents' work or similar, and it would have been a 286 or worse.

Although I suppose the 486 came out in '89, it was rare to see it in the schools that I went to, or in my friends' homes. Similarly with VGA and SVGA (and decent sound cards!), it took several years to become affordable and mainstream. But when they did, and when Pentiums started coming out, it was pretty much the death knell for the Amiga. I recall somberly looking at benchmarks of 486s, and comparing it to our pride and joy, a 68030-upgraded A1200, and realising that it was a losing game.

So you are absolutely right, though I think the timeline is probably a bit shifted depending on the country / economic conditions.