I have a similar impression of the 90s, though I've been skeptical of it since that happened to also be my childhood
But, in general, I do have a sense it was a uniquely optimistic decade for many people in the former First World, mainly because the Cold War ended and there was a sense that we had "won". Western Europe in particular demilitarized a lot as a result, the EU was formalized, the Good Friday Agreement was signed, Oslo Accords happened, end of apartheid etc.
For Americans I think 9/11 derailed things again.
Outside of the former First World, I'm not sure they'd see the 90s the same way.
but yeah it wasn't that great anywhere south of cancun or cairo