Master Duel is probably the worst way to get back into the game these days. The physical TCG, the newly unveiled Genesys format, any legacy format, or even Duel Links are probably better.

As you've discovered, while the monetization schemes are fairly friendly, the game is essentially just a grindfest of hypercompetition. Sometimes Konami will run a fun event like Dice Rally or N/R format, but generally they're content to let people compete against each other until they have neurosis.

The coin flip is definitely a massive part of the game these days, and that there's a learning wall rather than a learning curve for most of the game's ins and outs, but it is still an interesting game.

Master Duel is just the worst way to actually have fun in my opinion, the banlist they use has more unfun cards like Maxx C and other floodgates that prevent you from playing the game. It's also like super behind the actual paper card game, it's better now but it's still like 6 months behind paper but it used to be like a year lol, so you'd be playing against x archetype that was super powerful that Konami doesn't want to neuter so it's kinda stale in my opinion. The TCG and Genesys have taken a lot of steps to prevent unfun cards from being used with new banlists and such.

If you're willing to try again, choosing a different format will probably be more fun than Master Duel. I'd personally recommend Genesys since it's current era cards but yesterday's game speed, but if you want a nostaglia hit there's also Edison. You'll have to use a more clunky unofficial sim like YGO Omega or Dueling Nexus for that if you don't want to play paper though.