That’s not entirely true. I just ran a test scenario. Just for funsies, I used navigraph to plan some flights, and input them into the WT modded Longitude (edit: without selecting a route or destination from the world map.)

First I flew from Rivolli, 5S6 (which is actually KHRF now) landed just fine at Missoula (KMSO) with the RNAV Runway 30 approach. ATC guided me just fine, in it’s annoyingly automated janky yet still fun and distractingly great robo-company on an otherwise quiet flight. . .
After landing and parking, called for gas, then deleted the flight plan, and put in another segment from Missoula to Helena. Same deal. Used navigraph charts to plan, input into the garmin, then requested IFR clearance.
Wowsa. Worked just fine. Had robo-ATC with me the whole route, although the ILS Z on the 20 DME arc via NORRA doesn’t load in the sim properly, so I just re-requested the ILS Y with vectors (and flew the arc anyway as “vectors.”) and landed just fine.
So, it is possible to get ATC clearance, takeoff, land, get another, then repeat. . .at least with the pseudo default aircraft. Oddly, it didn’t log my TO’s or Landings.
But I digress. I guess my question is, is this duplicate-able with fancier jets, like the -146, or CRJ, or 737-700, or FBW or Fenix, or Salty, or Heavy 78? I know they are more complex how they handle flight management, and I know about pre-planning in the MSFS world map to “activate ATC” but programming over in the FMC/FMS/MCDU to align those planned routes with ATC, but then the link is broken after landing. Hmmmmm. Maybe allow flight planning from within the sim session? It’s obviously possible.
Anyway, if not, no worries. A skypilotYTS says, I’ll just exit to menu and pretending I’m running into the terminal for a bio-break, replan, and relaunch.