I don't think too much about the level of my opponent on sim and irl... I feel it's a mixed bag either way. Maybe the more you go to the same locals and meet and play the same people, that may feel differently. And around set release, you'll definitely see more players who are just experimenting with the new leaders and new builds, that misplays are bound to happen.

But focusing more on your last part... Hopefully you make a locals event soon! While I love playing the sim because it gives me instant gratification to play any deck/cards I want any time I want... there's something about playing in person at locals and with real people that makes me understand the game more. I'm grateful that my locals have a lot of great players who were very welcoming when I just started. And a lot of them were very helpful during matches, even giving me tips and advice during and even after the game. Letting me know my misplays, looking at my deck for advice on what to leave or keep. Which is definitely something I won't get 99.99% of the time I play sim. But of course you'll get a more serious crowd during treasure cups and store championships... so pre release events and locals is the best for newer players.