That’s just not true. And even if it was you would have to have 4 or 5 of those missions RNG’d to be exactly the same and all have 10,000 credit rewards which wasn’t often.
Ceres dark sector survival is 20,000 for 5 min. With a booster you get 40,000. Every 10 mins earning 80,000 credits early in the star chart was very easy. And it only got to lvl 20 Infested so it wasn’t even remotely difficult. Alerts never came close to that. Ever.
And ok, maybe op or who ever else isn’t to Ceres yet. If they weren’t to at least Saturn they wouldn’t ever have been seeing the random 10,