I don't even think this golden age actually exists today. Aask Google AI mode for the best product in some category - say, the best kitchen range - and it cites... a bunch of spammy "review" websites and a YouTube video.

If you're shopping around, an LLM you control can work for stuff like summarizing customer reviews or compiling a list of products with specific features (if you don't mind them being randomly wrong). But for general shopping advice / "plan my vacation" kind of queries, it's already firmly in the land of SEO-garbage-in-SEO-garbage-out.