So looking back to the Falcon 9, there were only 4 failures to complete orbital objectives across 503 launches and one of those was only a partial failure (main payload delivered successfully, but the secondary payload was not due to a single-engine failure). These failures were not consecutive (4th, 19th, what would have been the 29th and 354th). Now apart from the first launch or two (COTS Demo Flight 1 had some useful payload, but still seemed pretty disposable) these all had real payloads so they were less experimental than these Starship test flights.
If we compare to the propulsive landing campaign for the Falcon 9 1st stage it's a bit more favorable. The first 8 attempts had 4 failures, 3 controlled splashdowns (no landing planned) and 1 success. I think in general it felt like they were making progress on all of these though. Similarly for the Falcon 1 launches they had 3 consecutive failures before their first success, but launch 2 did much better than launch 1. Launch 3 was a bit of a setback, but had a novel failure mode (residual first stage thrust resulted in collision after stage separation).
Starship Block 2 has had 4 consecutive failures that seem to be on some level about keeping the propellant where it's supposed to be with the first 2 failures happening roughly in the same part of the flight and this 4th one happening during pre-launch testing.
If we compare to the propulsive landing campaign for the Falcon 9 1st stage it's a bit more favorable. The first 8 attempts had 4 failures, 3 controlled splashdowns (no landing planned) and 1 success. I think in general it felt like they were making progress on all of these though. Similarly for the Falcon 1 launches they had 3 consecutive failures before their first success, but launch 2 did much better than launch 1. Launch 3 was a bit of a setback, but had a novel failure mode (residual first stage thrust resulted in collision after stage separation).
Starship Block 2 has had 4 consecutive failures that seem to be on some level about keeping the propellant where it's supposed to be with the first 2 failures happening roughly in the same part of the flight and this 4th one happening during pre-launch testing.