Can we? Starships keep exploding. I get it, great engines are built on heaps of blown up engines. But are we there yet?
People have forgotten how much destructive testing NASA used to do back in the Apollo era (eg with the Ranger program, 9 were launched over 5 years, the first 5 were total failures, 6th was a partial failure).
SpaceX has pretty rapidly improved in Raptor reliability, we've gone from seeing them routinely spitting out green flames (ie eating themselves) on the early tests, to now routinely firing them on the test stand without issue (with the exceptions assumed to be when they're trying to probe the limits). We've gone from them having trouble lighting them reliably, to lighting and maintaining all engines at launch on both vehicles in the most recent test flight. Similarly it's been a while since we've seen a static fire where an engine failed to light. This is despite the constant performance upgrades pushing its already world leading specs even higher.
The most recent explosions were very likely not due to the engines. For the booster, iirc the theory based on the public data is that the oscillations due to some issue with the grid fin control system caused the propellants to slosh around very hard, damaging the plumbing, causing the engines to shut down and the booster to smash into the water. The Starship had a very visible leak under its skirt that caused it to be unable to maintain attitude, I think the theory with this is that it was a stuck or damaged valve in the RCS.
And, of course, as the other poster mentioned, they're almost at the point where what's failing is the reusability rather than launch, the only launch related milestone left to prove out is engine relight in vacuum. While they will probably figure out reuse eventually, it is not strictly necessary for HLS, especially as it pertains to the Starship itself (which is a much bigger challenge than the booster). The booster is the most expensive part of the vehicle, so their priority is to get reuse for it working. If they encounter significant hurdles with reusing the Starships, they can throw them away for early HLS launches and still be cheaper than SLS.
As far as controlling large numbers of engines and having them be cheap, restartable and throttleable, we have the Merlin in Falcon 9 and especially Falcon Heavy as an example. Heavy has to control 27 engines at liftoff. For powerful, highly efficient engines, we have the RS-25 in Shuttle/SLS and BE-4 in Vulcan/New Glen as additional examples.
Saturn V had zero failed launches
Also they blew up tons of F1 engines during testing. They never got the POGO issues fixed.
I really don't understand why people make these arguments. SpaceX is explicitly saying they dont want to spend money proving everything works the first time.
We may get there eventually, perhaps even with starship, but the fact remains that in 60 years after Apollo we don't have a comparable heavy rocket.