They lying to you
But on a serious note, CMC is just okay. It's average at best. Forbidden Memories is also not that great of a game. I hate to say it but I'm critical of the things I love, pretty much 90% of old Yu-Gi-Oh games are abysmal. The difficulty is off the rocker (and no, it's not the good kind of difficulty, it's the kind where enemies have decks leagues stronger than yours so you just have to grind for hours on end mindlessly)
Over the Nexus is just overall the better version of Reverse of Arcadia, sure different story and different card pool (kinda) but I would replay Over the Nexus and wouldn't replay Reverse of Arcadia, cause they're virtually almost the same game.
People played DoD recently thanks to the new collection, and realise that it's not that crazy of a game. It's just another whatever mediocre mindless grindfest.
Nightmare Troubadour is good, just a little bit repetitive and it's best feature (finding duelists) is also it's weakest feature due to the fact you're gonna have to duel the same guy a hell of lot of times
Duelist of Roses is peak tho, no words on that one, the Tag Force games, again, are also ALMOST identical say for being set in different parts of the animes story and also having different card pools, but I love those games to death. They're what I'd say is a good balance between grind and fun gameplay, where the game is long but not because you're mindlessly grinding all the time, rather because there's a fuck load of content in it. I can't pick a favourite from the GX line, I love all of them. Even the 5D's ones are pretty alright (although again, WC11 which is Over the Nexus btw, is probably the best 5D's game and likely my favourite Yu-Gi-Oh game)
Another great game is Duel Acadmy on GBA and Spirit Caller on DS. Regardless of what people say, Spirit Caller is legit just Nightmarr Troubadour but GX and it has a couple of improvements on the gameplay. And a few downsides compared to the first game but hey, we're not exactly picking from gold here we take what we can get.
Sorry for the extremely long response, I just think if we actually unironically let newer players into playing stuff like Forbidden Memories I think they'll hate the game more than they already do. The actual game seems complex for beginners as is, FM and a lot of older games like it are even worse mechanically.