I think your notion of "the truth" is heavily influenced by exactly the context she's pointing at. Google and Meta's algorithmic rankings aren't "the truth", and "the truth" doesn't change on each regular parameter rebalancing. Those algorithms were built by a relatively small number of people from a narrow set of backgrounds who were focused on maximizing usage and revenue, and the bulk of "the truth" they contain is about that.
One thing importantly different about our age is context collapse. With communication costs and marginal costs near zero, a global service is easier and cheaper to build than local ones with equivalent coverage. It's as if we've taken every ecosystem in the world and dumped it onto the San Francisco peninsula to fight it out to discover "the truth" about what plants and animals are "best".
What's different about those small locales and villages is that each one of them naturally had its own values. Skills and tastes co-evolved. Schools of thought were born and elaborated. Communication and movement between locales gave useful exchange and inspiration, but generally weren't enough to swamp variation.
In the pre-web era, the question of, say, whether Irish music was better than Spanish music would be seen as kind of a dumb question to take any more seriously than for an entertaining argument. But having put everything in Meta's global blender and reduced it to counting updoots, the ever-present metrics purport to provide "the truth" to questions like that.
They don't, of course. But they do place a much larger burden on us to recognize that not everything that goes up and to the right is an unalloyed good.