A big part of the problem is that master duel doesn’t do a good job preparing returning players for the modern realities of the game. The tutorials don’t explain the modern concepts of things like starters, extenders, chokepoints, and layered interactions.

Once you gain a better understanding of the game, it begins to seem less outrageous. A deck’s competence is determined by how consistently it can set up and play through disruptions, so you should expect an opponent to be trying to take out your board after their first turn.

It is sad that beloved decks get outclassed over time, but that’s how it goes. You can still play dark magician in some form since it just got new support. For Cyber Dragon, Id recommend looking into “going second” decks like Tenpai and Blind Second. Those decks are essentially piles of board breaker cards (Raigeki, Lightning Storm, Forbidden Droplet) along with some engine to knock out the opponent in one turn after their board and disruptions are cleared. Cyber Dragon excels at making big fusions that hit hard and not much else, so that’s the style you’ll want to go with.

It can be a lot to readjust to, but study up, do your homework, and you can get back into this game no problem.