The biggest issue is payload. Right now they’re launching with very light payloads, way less than the Saturn V or even the Falcon. Definitely short of their goals. They’ve never demonstrated a real payload weight. Until this happens their progress is illusory and a skeptic would claim their engines can’t take a real launch payload weight.
That is a completely un skeptical estimate of the payload capacity: were the satellites fully fueled? If they carried a 50% load of fuel that would knock off half a ton from each satellite. Was the upper stage fully fueled, including the fuel needed to return to where it was launched? If not, there's enough fudge in the numbers that the actual payload capacity could be zero, if not for scavenging weight from other parts of the mission plan.
Is skepticism warranted? At least they didn't call it Fully Satellite Deploying.
The only way the payload is much lower than 52 tons is if SpaceX is lying about the mass of their satellites. That seems unlikely, as correct masses are required for FAA debris assessment.
Each Starlink V3 satellite weighs approximately 2 tons. They use ion thrusters for propulsion, so propellant on each satellite is 50-100kg, not half a ton. The current payload bay can hold around 60 V3 satellites, so they'd launch fewer of them (as they did in this launch) instead of putting partially fueled satellites into orbit.
A tower catch and an ocean splashdown require the same amount of propellant. The only difference is when the deorbit burn happens. Yes there will be some boil-off as the ship stays in orbit for longer, but a day in orbit would lose around 0.5% of the propellant. According to the live stream, both the booster & ship were loaded to about 98.5% of capacity. And filling the tanks completely would give them more payload capability, not less.
If you need to see a satellite deploy followed by a tower catch to be convinced of their payload numbers, then you're asking for evidence that doesn't exist yet. But I'd be happy to bet on that. How about this: If before December 31st, 2027, SpaceX deploys a payload greater than 50 tons from Starship while recovering both the booster & ship (I assume via tower catch. Fishing out of the water doesn't count.) you pay me $1,000. If that doesn't happen, I pay you $1,000. If you like, we could both choose a charity and the loser donates to the charity of the winner's choosing.
The Starlink V3 sats launched today are much bigger and heavier than the Starlink satellites they've been launching on Falcon. Even if they fit within the Falcon fairing, they'd be too heavy to launch on F9.
> skeptic would claim their engines can’t take a real launch payload weight.
full duration full throttle burns of Raptor3 are common and I'm pretty sure a part of qc for each new engine anyway. Payload weight doesn't strain the engines, once they're throttled at 100% then they're throttled at 100% no matter how much or how little payload there is.