Outside of Cloudian/Ra and Ojamas, most decks recommended were either paywalled (S.M.) or from old boxes (Hourus). Don't blame people when they don't have much to work with, at least with any consistency.
His lv40 deck was too powerful for most farming decks. Cloudian Ra and Ojama didn't work well prior to the balancing, your only choice to farm him was the ultra expensive silent magician farming deck.
I was having some pretty consistent luck with my inzektor deck prenerf, and I would assume any deck with direct attacks would have worked similarly just as good.
If people are still having trouble with Yami, I highly recommend and inzektor deck if you have the cards. It’s rare the duel lasts beyond the second turn, and even then you still have a good matchup.