I think a lot of the scepticism is a counterpoint to the unbridled starry eyed optimism. Building this thing is hard and will remain hard. Having achieved 80% is only a weak indicator that they will achieve the remaining 20%.

And yet every news for the past 5 years or whatever has been "wow it's a runaway success and basically done". Something flies? Great! Something blows up? Ooh actually that's even better because [convoluted argument] and Starship will fly in 6 weeks time.

I wish them well. The crazy optimism still strikes me as a bit mad.