That was a deliberate purge of remaining methane still in the tank. They couldn't vent it without burning it off - risk of accumulations somewhere and explosion, which is worse than a fire.
Not sure but I think the booster catch today is just "one small step" and the long-game hasn't been played yet. They also say they will land Starships on the Moon and it's not clear to anyone how that's supposed to work, either. But SpaceX has figured out so many other novel developments in spaceflight, they have earned some trust that the plan on their drawing board could be a good one. So what could that be? The question of landing anything on the Moon or Mars has remained extremely risky and difficult, even after decades of trying by NASA, USSR, Japan, China, India and others. Seems to invite a novel solution since the tried-and-true solutions require very high complexity (Apollo LM) to be guaranteed successful. Considering all that, my guess (not sure if there's been an official statement from Spacex on this) is that SpaceX has decided that they will prefer to build infrastructure on the Moon or Mars before attempting to land humans on it. Their decades-long practice of guiding rockets to controlled landings with increasing precision and repeatability suggests this strategy is preferred. While other space agencies will probably try to continue landing spacecraft on raw terrain in the coming decade, I expect SpaceX will minimize that or avoid it altogether. Their landing system for the Moon/Mars probably won't look exactly like Mechazilla Chopsticks, and nothing like a drone ship on the ocean, but I'll bet they won't just drop down on open regolith.
![[medal]](/data/assets/smilies/medal.gif "[medal] [medal]")
. More hard work to do.
