Cryogenic refueling is the real choke point before anything beyond LEO counts as a plan.
Starship still needs the first full ship-to-ship cryogenic transfer before Mars missions become real logistics, not just launch tests. No two vehicles have docked and moved propellant between them as of Flight 13 in July. Https://spacedaily.com/t-starship-13-test-flights-orbital-refueling-mars-hurdle/