That article doesn’t say it didn’t exist in sufficient quantities, but rather that the factors that affect this question are still largely unknown, and hotly debated. If certain things were the case, then it is likely it would have existed in those quantities - and if these things weren’t the case - then it didn’t. It’s a typical article giving an overview of a scientific argument by presenting both sides pro and con, without coming down hard on a particular conclusion.
But the relevance of all of this thing about borate and it’s stabilizing effect on ribose is based on another assumption, which is also an unknown, which is that the RNA-world somehow began by a chemical process that had ribose as an intermediate that would need to be stabilized against competing products(produced in something like the formose reaction), so it could later be joined to the different nitrogenous bases through a glycosidic bond, which is also heavily disputed.
Many others have argued there are other ways to make RNA than this.
So if you’re going to say there couldn’t have been an RNA world, you need to show a lot of evidence that settles a lot of big unknowns about the early Earth and it’s environments, and about abiotic organic chemistry. Merely pointing to one or both sides in a lot of different debates for a selection of quotations arguing that opposing views are unlikely given assumption X does not constitute meaningful discussion.
At any given moment in science there is some advancing frontier of research, where certain topics are hotly contested, and in those moments you can find statements by people on different sides arguing that the views of their opposition are somehow all unlikely, implausible, or impossible. Yet such debates usually eventually settle, and one side comes out being right and the other side wrong. You can go pick quotes from the period when the mechanism of oxidative phosphorylation was unknown and a subject of hot contest, to “prove” that (taking the arguments from both camps) life must be impossible, because apparently there’s no way any mechanism of oxidative phosphorylation could possibly occur and suffice to power life. But one side won that debate eventually, and the other side lost, and we now know ATP is generated by chemiosmosis.
You can find lots of papers arguing that “the other guy’s scenario for the RNA world is wrong and here’s why”, it’s just that it’s all based on innumerable assumptions that have yet to be settled(some argue there was no dry land at all, not even volcanoes of any appreciable size, which would basically rule out all versions that involve evaporation and wet-dry cycles, leaving only submarine hydrothermal vents among presently conceived settings for life’s emergence), and are likely to remain unknowns for quite a while, because there’s scant little evidence for what the earliest periods in Earth’s history was really like.