People may find this hard to believe (or maybe not), but one reason why modern flight sims of modern subjects has fallen away is licensing. Somewhere along the way the aircraft industry, just like the car industry, decided you cannot go around making things using their products without paying them for the honor. And since realistic modern flight sims do not generally sell by the truckload, developers are less inclined to pay for licensing.
And since pretty much all American aviation, apart from Lockheed, is now owned by Boeing- and Boeing being a pack of assholes...you can see the problem. For example, Boeing owns the WW2 Mustang fighter. Despite the fact that it was paid for in wartime by tax payers, not just in the USA, but the Commonwealth as well. It should be public domain. But small companies can not afford to make plastic model kits of the Mustang because they cannot afford the Boeing license. So what would Boeing now charge for a license for the Falcon? It's not just Boeing either. I've worked in the aircraft industry for 25 years, and I assure you it is one of the dirtiest industries in the world.