The Starship launch of April 20 was a test for the BFR (Big Falcon Rocket) and Starship. It was considered a major success as it was able to launch off the rocket pad with no major issues (some of the engines did fail on the first stage but the Launch Vehicle was able to continue). One thing to note is the current test of Starship was to launch and possibly test proper separation (which this launch failed iirc). It was never meant to go and complete a full orbit. This launch was the first test of the entire system (BFR and Starship together), so it acts more of "how far can we go with our current progress?"

Almost all unmanned rockets have a faliure mode of exploding, but this is usually done above a safe area. A bunch of debris falling down is a lot safer than a whole Rocket, loaded with explosive fuel. Starship had exploded above the Gulf of Mexico, far away from any pockets of civilization. Keep in mind, to do this launch, they would have to had clearance from government agencies (not sure which one specifically, probably NASA?) to perform said launch.

I guess one major criticism I have of SpaceX's trial and error method is that it does cause more environmental damage than NASA's method (slower development but leads to less lost of vehicles).

Take this with a grain of salt, as I am no means an expert, just an Aerospace enthusiast and am going by what I recall.