I just cannot wrap my head around why a parachute can't get this job done. They are able to work well enough to stop fragile humans legs from breaking...but somehow useless for robust metal machines?

I think Space X is really playing is the Military Industrial Complex boondoggle game. As In Space X's real customer is the DoD where they are selling rockets to the military for 10x the cost of what they need to be to do the mission.

Kind of like that other boondoggle, the F-35, which can be beaten in a dogfight by an F-15 adopted in 1976, the F-16 the US has exported to 20+ nations, and every Air-to-Air combat jet Russia has. Meanwhile they cost something like $100 million a peace while Russia's answer, the Su-57 in coming in "hot" at $30 million.

The F-35 doesn't exist to win a war. SAM's are more effective in killing enemy aircraft, and helicopters are better at killing ground units. Further stealth doesn't begin to work as advertised, considering steath aircraft have been shot down with 1950's soviet equipment. So why does it exist? Why to sell the DoD something that costs $100 million a pop and needs something insane like an additional $20 million per plane per year to keep operational.

Its the same insane reason why the USA's main battle tank has a turbine engine that needs a complete rebuild and GUZZLES fuel just idling, when EVERY other tank in history uses a diesel truck engine that is 20x as fuel efferent and 100x more reliable. Why? Well they need a new engine every 700 hours of operation. And to quote...

"The Army Tank-automotive and Armaments Command estimates that the Honeywell AGT1500 gas turbine engine accounts for about 42 percent of overall M1 support costs. “It’s the number one target for reducing the cost of operating the tank,” says Abrams Product Manager Lt. Col. Michael Flanagan."

This is how and why this kind of stuff is made, it has built-in revenue streams.