Your presumption of a collective "we" is at the root of the problem: versioning is one of those things in development where the same word can mean very different things to different people (see also: agile, automated testing). Prior to semantic versioning, there was an approach that looked like an agreed-upon standard to consumers of software packages/ libraries/ APIs but was not.

On one extreme you had certain developers (who I am sympathetic to because it's my personality) who were loath to ever label something 1.0 because it implies Doneness and a freedom from bugs that can never be so. On the other side you had people at chop shops who would bump the major version of some boxed product every time they fixed two bugs. Even if you as a good developer did the research to discover that 0.7.6 of Package A was solid and 5 years older than Package B 7.6, there was a good chance someone above you would declare 7.6 > 0.7.6 and that it was paid-for software so "We can get support from them" and force you to work with a shittier product.

So "we" developers do what we almost always do: we cast about for a better solution and landed on one that made the meaning of version numbers opaque to anyone outside the guild of mages writing code.

In short, semantic versioning may suck hard, but it sucks less.