I actually got my first Yakuman a couple months ago!
It was in Super Real Mahjong PIV on the Super Famicom. I looked it up later and according to the Japanese wiki I checked, it doesn't alter the odds in favor of the player at all, so as near as I can tell this was totally legitimate.
I was going for this Chinitsu Ryanpeikou. I riichi'd and got the yasume, but the uradora ended up being the yasume, and I got kazoe!

I've been playing mahjong since I think around 2013, fairly casually but I get a little better every year. I've gotten a few yakuman tenpai in that time but this is the first one that actually materialized.
I was super obsessed with the idea of getting a yakuman as I started, but as time went on I've just focused more on winning each individual game. I would have been totally happy with Sanbaiman here because it would have been enough points for me to finish the whole game. Really fun surprise for me to end the game with.