I have a lot of friends in the manufacturing business that range from self-employed to military-backed conglomerates. None of them use this tool. Are they all Luddite idiots, or is this Amazon search tool, backed by their swiss-cheese supply chain, just not that useful?
I think it's the same as the overall enshitification of all products and product quality. Consumers now value cheap fast shipping and low prices over everything else. Amazon delivers that, with the tradeoffs in product quality, support, etc. Other things are low quality too, like the product listings themselves. Often, for example, the listed dimensions or other specs (thread type, grade strength, etc) are missing or just wrong. That's much less true for sites like McMaster. But nobody values that anymore.
Easier but they are no McMaster, by a long shot.