I’ve been doing MSflight sim since it’s very first edition 40 or so years ago. At this stage all I sim fly are jumbos. I know most of the speeds and flap settings etc for landing Boeing, Airbus etc. And all the procedures to land like butter on bread.
I play with all realism on with absolutely no aides enabled. So yeah, I could land it even without ATC as long as I have the right chart and clearance. After all, I land them all the time in my sim.
Actual pilots say that flight sims are pretty accurate, so if you can fly one of those, you can fly a real plane for the most part. But the devil is in the details. What do you do when there are cross-winds, for example? Little known factors that don’t happen very often?